chroot_version_hooks.d: drop support for upgrading SDKs pre-2019

Punt a lot of old upgrade hooks that only get used for SDKs that were
created before 2019 and have not been upgraded since.  The tooling will
already detect this scenario (because the upgrade hooks are missing) and
throw an error telling the user to recreate the SDK.

We know that people aren't doing this because apparently it's been broken
for sometime now when trying to upgrade with an old version of portage.
Since no one has complained, rather than try and fix a scenario that no
one is testing, just drop it all.

BUG=None
TEST=precq passes

Change-Id: I2aeea1a0535d94bf937e4fe3464a046a6e87e0be
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/2028989
Reviewed-by: Chris McDonald <cjmcdonald@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
diff --git a/chroot_version_hooks.d/109_convert_main_boards_to_freon b/chroot_version_hooks.d/109_convert_main_boards_to_freon
deleted file mode 100644
index be12642..0000000
--- a/chroot_version_hooks.d/109_convert_main_boards_to_freon
+++ /dev/null
@@ -1,26 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  peppy
-  link
-  panther
-  panther_embedded
-  panther_moblab
-  panther_goofy
-  zako
-  mccloud
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/110_convert_monroe_to_freon b/chroot_version_hooks.d/110_convert_monroe_to_freon
deleted file mode 100644
index dafe5a1..0000000
--- a/chroot_version_hooks.d/110_convert_monroe_to_freon
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARD=monroe
-
-if [[ -d /build/${BOARD} ]]; then
-  /mnt/host/source/chromite/bin/setup_board \
-    --board=${BOARD} \
-    --skip-chroot-upgrade \
-    --regen-configs
-fi
diff --git a/chroot_version_hooks.d/111_monroe_go_public b/chroot_version_hooks.d/111_monroe_go_public
deleted file mode 100644
index c6a3e0c..0000000
--- a/chroot_version_hooks.d/111_monroe_go_public
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the public overlay.  Make sure we regen the
-# boards profile settings and such so we pull in the public bits.
-
-for b in monroe; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/112_nyan_big_go_public b/chroot_version_hooks.d/112_nyan_big_go_public
deleted file mode 100644
index 2264c66..0000000
--- a/chroot_version_hooks.d/112_nyan_big_go_public
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the public overlay.  Make sure we regen the
-# boards profile settings and such so we pull in the public bits.
-
-for b in nyan_big; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen_configs
-  fi
-done
diff --git a/chroot_version_hooks.d/113_uboot_netboot_for_daisy b/chroot_version_hooks.d/113_uboot_netboot_for_daisy
deleted file mode 100644
index 40ebb9f..0000000
--- a/chroot_version_hooks.d/113_uboot_netboot_for_daisy
+++ /dev/null
@@ -1,17 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# daisy_spring got a new package.use for supporting uboot netboot properly,
-# CL:242831.
-# Due to these changes, etc/make.profile becomes invalid and
-# must be re-generated.
-
-for b in daisy_spring; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/114_more_freon_boards b/chroot_version_hooks.d/114_more_freon_boards
deleted file mode 100644
index 0c4fc31..0000000
--- a/chroot_version_hooks.d/114_more_freon_boards
+++ /dev/null
@@ -1,22 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  falco
-  falco_li
-  wolf
-  leon
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/115_veyron_go_freon b/chroot_version_hooks.d/115_veyron_go_freon
deleted file mode 100644
index 4c865c3..0000000
--- a/chroot_version_hooks.d/115_veyron_go_freon
+++ /dev/null
@@ -1,30 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  veyron
-  veyron_brain
-  veyron_danger
-  veyron_gus
-  veyron_jaq
-  veyron_jerry
-  veyron_mighty
-  veyron_minnie
-  veyron_pinky
-  veyron_remy
-  veyron_rialto
-  veyron_speedy
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/116_update_protobuf b/chroot_version_hooks.d/116_update_protobuf
deleted file mode 100644
index 96683cb..0000000
--- a/chroot_version_hooks.d/116_update_protobuf
+++ /dev/null
@@ -1,18 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Having revved dev-libs/protobuf to 2.6.1 in the SDK, we need to rebuild stuff
-# that dynamically links against the libraries it installs.
-# Unfortunately, using the in-build emerge logic for rebuilding all the
-# reverse-dependencies of protobuf seems to blow up pretty terribly
-# (including gcc and icedtea for some reason?) so let's just rebuild the
-# things we know to be required.
-sudo emerge \
-  chromeos-base/libchrome \
-  chromeos-base/libchromeos \
-  chromeos-base/metrics \
-  chromeos-base/update_engine \
-  dev-libs/protobuf \
-  dev-libs/protobuf-python
-
diff --git a/chroot_version_hooks.d/117_samus_go_public b/chroot_version_hooks.d/117_samus_go_public
deleted file mode 100644
index 6bb8864..0000000
--- a/chroot_version_hooks.d/117_samus_go_public
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the public overlay.  Make sure we regen the
-# boards profile settings and such so we pull in the public bits.
-
-for b in samus; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/118_newlib_SLOT b/chroot_version_hooks.d/118_newlib_SLOT
deleted file mode 100644
index 2572909..0000000
--- a/chroot_version_hooks.d/118_newlib_SLOT
+++ /dev/null
@@ -1,9 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# The newlib package changed SLOT on us, so auto clean older versions.
-
-sudo emerge -Cq \
-  cross-arm-none-eabi/newlib:arm-none-eabi \
-  cross-nds32le-cros-elf/newlib:nds32le-cros-elf || :
diff --git a/chroot_version_hooks.d/119_rambi_ivb_boards_to_freon b/chroot_version_hooks.d/119_rambi_ivb_boards_to_freon
deleted file mode 100644
index 7123101..0000000
--- a/chroot_version_hooks.d/119_rambi_ivb_boards_to_freon
+++ /dev/null
@@ -1,30 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  candy
-  clapper
-  enguarde
-  expresso
-  glimmer
-  gnawty
-  kip
-  parrot_ivb
-  rambi
-  squawks
-  swanky
-  winky
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/120_more_rambi_boards_to_freon b/chroot_version_hooks.d/120_more_rambi_boards_to_freon
deleted file mode 100644
index 42ca025..0000000
--- a/chroot_version_hooks.d/120_more_rambi_boards_to_freon
+++ /dev/null
@@ -1,22 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  banjo
-  cranky
-  ninja
-  sumo
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/121_clean_emacs b/chroot_version_hooks.d/121_clean_emacs
deleted file mode 100644
index e992b07..0000000
--- a/chroot_version_hooks.d/121_clean_emacs
+++ /dev/null
@@ -1,16 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Clean out old emacs versions that people installed by hand.  Since they've
-# moved and have blockers, portage often won't auto-resolve the upgrade.
-# This doesn't mean people need to manually recover -- normally they will have
-# virtual/emacs installed which will automatically pull back in emacs.
-
-packages=(
-  app-editors/emacs
-  app-admin/eselect-ctags
-  app-admin/eselect-emacs
-)
-
-exec sudo qmerge -yqU "${packages[@]}"
diff --git a/chroot_version_hooks.d/122_update_sdk_profile b/chroot_version_hooks.d/122_update_sdk_profile
deleted file mode 100644
index 90d2d93..0000000
--- a/chroot_version_hooks.d/122_update_sdk_profile
+++ /dev/null
@@ -1,27 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Make sure the sdk profile is in the new location.
-
-src='/etc/make.profile'
-dst='/etc/portage/make.profile'
-
-# If the system has already been upgraded, nothing to do.
-if [[ ! -e ${src} ]]; then
-  exit 0
-fi
-
-# In case it exists (who knows why!), clear it out.
-if [[ -L ${dst} ]]; then
-  sudo rm -f "${dst}"
-fi
-if [[ -e ${dst} ]]; then
-  sudo rm -rf ${dst}
-fi
-
-# Move old path to new one if it exists (initial sdk setup might already
-# have migrated it for us).
-if [[ -e ${src} ]]; then
-  sudo mv "${src}" "${dst}"
-fi
diff --git a/chroot_version_hooks.d/123_jre_update b/chroot_version_hooks.d/123_jre_update
deleted file mode 100644
index ef507fa..0000000
--- a/chroot_version_hooks.d/123_jre_update
+++ /dev/null
@@ -1,14 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Manually force java to be upgraded to the new version when updating.
-
-sudo CLEAN_DELAY=0 emerge -Cq \
-  '<dev-java/icedtea-bin-7' \
-  '<virtual/jre-1.7' \
-  '<virtual/jdk-1.7'
-if ! portageq has_version / '>dev-java/icedtea-bin-7'; then
-  sudo emerge -1ug '>dev-java/icedtea-bin-7'
-fi
-sudo java-config --set-system-vm 1
diff --git a/chroot_version_hooks.d/124_update_make_conf_target b/chroot_version_hooks.d/124_update_make_conf_target
deleted file mode 100644
index be2905e..0000000
--- a/chroot_version_hooks.d/124_update_make_conf_target
+++ /dev/null
@@ -1,17 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We've deleted all the make.conf.$ARCH-target files.  Regen the existing
-# make.conf symlinks to point to the generic one now.
-
-target='/usr/local/portage/chromiumos/chromeos/config/make.conf.generic-target'
-
-for sysroot in /build/*; do
-  conf="${sysroot}/etc/make.conf"
-  if [[ -L "${conf}" ]]; then
-    sudo ln -sf "${target}" "${conf}" &
-  fi
-done
-
-wait
diff --git a/chroot_version_hooks.d/125_regenerate_make_conf_board_setup b/chroot_version_hooks.d/125_regenerate_make_conf_board_setup
deleted file mode 100644
index 14afdbe..0000000
--- a/chroot_version_hooks.d/125_regenerate_make_conf_board_setup
+++ /dev/null
@@ -1,18 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We added an ARCH field to make.conf.board_setup. If that field is not set in
-# one of the board, regenerate the sysroot's configuration.
-# The user might have lots of boards set up. As we added this field few months
-# ago, only set up the boards that do not have that field.
-
-for sysroot in /build/*; do
-  make_conf="${sysroot}/etc/make.conf.board_setup"
-  if [[ -f "${make_conf}" ]] && ! grep -q "ARCH=" "${make_conf}"; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=$(basename "${sysroot}") \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/126_add_eclass_overlay b/chroot_version_hooks.d/126_add_eclass_overlay
deleted file mode 100644
index 22fa305..0000000
--- a/chroot_version_hooks.d/126_add_eclass_overlay
+++ /dev/null
@@ -1,20 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# crossdev generates the chroot's layout.conf file, which lists overlays
-# to be used while emerging packages into the chroot (for instance, toolchains).
-# In order to add eclass-overlay to that overlay list, we need to patch
-# crossdev.
-
-# Add the extra overlay just for now.
-conf='/usr/local/portage/crossdev/metadata/layout.conf'
-if ! grep -qs '^masters =.*eclass-overlay' "${conf}"; then
-  sudo sed -i \
-    -e '/^masters =/s:$: eclass-overlay:' \
-    "${conf}"
-fi
-
-if ! portageq has_version / '>=sys-devel/crossdev-20150602'; then
-  sudo emerge -1ug sys-devel/crossdev
-fi
diff --git a/chroot_version_hooks.d/127_rengenerate_board_config_lakitu b/chroot_version_hooks.d/127_rengenerate_board_config_lakitu
deleted file mode 100644
index 9581530..0000000
--- a/chroot_version_hooks.d/127_rengenerate_board_config_lakitu
+++ /dev/null
@@ -1,13 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We switched lakitu from make.conf to make.defaults
-# This broke incremental builds because make.conf.board still points to the
-# non-existent make.conf
-if [ -d /build/lakitu ]; then
-  /mnt/host/source/chromite/bin/setup_board \
-    --board lakitu \
-    --skip-chroot-upgrade \
-    --regen-configs
-fi
diff --git a/chroot_version_hooks.d/128_quawks_and_stout_to_freon b/chroot_version_hooks.d/128_quawks_and_stout_to_freon
deleted file mode 100644
index 3ed94fd..0000000
--- a/chroot_version_hooks.d/128_quawks_and_stout_to_freon
+++ /dev/null
@@ -1,20 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  quawks
-  stout
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/129_exynos_to_freon b/chroot_version_hooks.d/129_exynos_to_freon
deleted file mode 100644
index 2604a08..0000000
--- a/chroot_version_hooks.d/129_exynos_to_freon
+++ /dev/null
@@ -1,24 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  daisy
-  daisy_skate
-  daisy_spring
-  peach
-  peach_pi
-  peach_pit
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/130_pineview_and_sandybridge_to_freon b/chroot_version_hooks.d/130_pineview_and_sandybridge_to_freon
deleted file mode 100644
index 7e1367d..0000000
--- a/chroot_version_hooks.d/130_pineview_and_sandybridge_to_freon
+++ /dev/null
@@ -1,28 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  butterfly
-  lumpy
-  parrot
-  parrot-ivb
-  stumpy
-  x86-alex
-  x86-alex-he
-  x86-mario
-  x86-zgb
-  x86-zgb-he
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/131_pineview_and_sandybridge_not_freon b/chroot_version_hooks.d/131_pineview_and_sandybridge_not_freon
deleted file mode 100644
index 7e1367d..0000000
--- a/chroot_version_hooks.d/131_pineview_and_sandybridge_not_freon
+++ /dev/null
@@ -1,28 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  butterfly
-  lumpy
-  parrot
-  parrot-ivb
-  stumpy
-  x86-alex
-  x86-alex-he
-  x86-mario
-  x86-zgb
-  x86-zgb-he
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/132_pineview_and_sandybridge_to_freon_again b/chroot_version_hooks.d/132_pineview_and_sandybridge_to_freon_again
deleted file mode 100644
index 7e1367d..0000000
--- a/chroot_version_hooks.d/132_pineview_and_sandybridge_to_freon_again
+++ /dev/null
@@ -1,28 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  butterfly
-  lumpy
-  parrot
-  parrot-ivb
-  stumpy
-  x86-alex
-  x86-alex-he
-  x86-mario
-  x86-zgb
-  x86-zgb-he
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/133_pineview_and_sandybridge_unmerge_kernel_3_4 b/chroot_version_hooks.d/133_pineview_and_sandybridge_unmerge_kernel_3_4
deleted file mode 120000
index 1acf6cc..0000000
--- a/chroot_version_hooks.d/133_pineview_and_sandybridge_unmerge_kernel_3_4
+++ /dev/null
@@ -1 +0,0 @@
-135_clean_linux-3.4
\ No newline at end of file
diff --git a/chroot_version_hooks.d/135_clean_linux-3.4 b/chroot_version_hooks.d/135_clean_linux-3.4
deleted file mode 100644
index 2614f57..0000000
--- a/chroot_version_hooks.d/135_clean_linux-3.4
+++ /dev/null
@@ -1,20 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# The linux-3.4 kernel is no longer used so make sure it gets cleaned
-# out for existing devices.
-
-packages=(
-  sys-kernel/chromeos-kernel
-)
-
-for sysroot in /build/* /; do
-  (
-  if ROOT="${sysroot}" qlist -ICe "${packages[@]}" >&/dev/null; then
-    info "Cleaning ${packages[*]} from ${sysroot}"
-    sudo ROOT="${sysroot}" qmerge -yqU "${packages[@]}"
-  fi
-  ) &
-done
-wait
diff --git a/chroot_version_hooks.d/136_samus_inherit_chipset_bdw b/chroot_version_hooks.d/136_samus_inherit_chipset_bdw
deleted file mode 100644
index ec1710d..0000000
--- a/chroot_version_hooks.d/136_samus_inherit_chipset_bdw
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We are now inheriting chipset-bdw from overlay-samus. We need to regen
-# the config so Portage can find chipset-bdw properly.
-
-for b in samus; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/137_unmerge_libchromeos b/chroot_version_hooks.d/137_unmerge_libchromeos
deleted file mode 100644
index 112888c..0000000
--- a/chroot_version_hooks.d/137_unmerge_libchromeos
+++ /dev/null
@@ -1,31 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Remove chromeos-base/libchromeos as it is being replaced by libbrillo.
-opkg="chromeos-base/libchromeos"
-
-export CLEAN_DELAY=0
-
-update() {
-  local root=$1 board=$2 emerge
-
-  if [[ -z ${board} ]]; then
-    board="root"
-    emerge="sudo -E emerge"
-  else
-    emerge="emerge-${board}"
-  fi
-  if portageq has_version ${root} ${opkg}; then
-    ${emerge} -Cq ${opkg}
-  fi
-}
-
-update / &
-
-for board_root in /build/*; do
-  board=${board_root##*/}
-  update ${board_root} ${board} &
-done
-
-wait
diff --git a/chroot_version_hooks.d/138_amd64_and_x86_generic_to_freon b/chroot_version_hooks.d/138_amd64_and_x86_generic_to_freon
deleted file mode 100644
index 46e2ecb..0000000
--- a/chroot_version_hooks.d/138_amd64_and_x86_generic_to_freon
+++ /dev/null
@@ -1,20 +0,0 @@
-# Copyright 2016 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  amd64-generic
-  x86-generic
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/139_unmerge_libchrome b/chroot_version_hooks.d/139_unmerge_libchrome
deleted file mode 100644
index 20fd14c..0000000
--- a/chroot_version_hooks.d/139_unmerge_libchrome
+++ /dev/null
@@ -1,32 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Remove old version of chromeos-base/libchrome as it is being uprevved to a new
-# revision and will use a different slot.
-opkg="chromeos-base/libchrome"
-
-export CLEAN_DELAY=0
-
-update() {
-  local root=$1 board=$2 emerge
-
-  if [[ -z ${board} ]]; then
-    board="root"
-    emerge="sudo -E emerge"
-  else
-    emerge="emerge-${board}"
-  fi
-  if portageq has_version ${root} ${opkg}; then
-    ${emerge} -Cq ${opkg}
-  fi
-}
-
-update / &
-
-for board_root in /build/*; do
-  board=${board_root##*/}
-  update ${board_root} ${board} &
-done
-
-wait
diff --git a/chroot_version_hooks.d/140_baseboard_chipset_inheritance_fix b/chroot_version_hooks.d/140_baseboard_chipset_inheritance_fix
deleted file mode 100644
index 352b222..0000000
--- a/chroot_version_hooks.d/140_baseboard_chipset_inheritance_fix
+++ /dev/null
@@ -1,38 +0,0 @@
-# Copyright 2015 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Several boards need to have their config regenerated due to structural
-# changes in the overlay.
-
-BOARDS=(
-  cyan
-  glados
-  kunimitsu
-  strago
-  auron
-  jecht
-  reef
-  chell
-  cave
-  lars
-  sentry
-  celes
-  edgar
-  ultima
-  terra
-  banon
-  reks
-  setzer
-  umaro
-  wizpig
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/141_unmerge_libchrome b/chroot_version_hooks.d/141_unmerge_libchrome
deleted file mode 120000
index b93eefc..0000000
--- a/chroot_version_hooks.d/141_unmerge_libchrome
+++ /dev/null
@@ -1 +0,0 @@
-139_unmerge_libchrome
\ No newline at end of file
diff --git a/chroot_version_hooks.d/142_unmerge_libchrome b/chroot_version_hooks.d/142_unmerge_libchrome
deleted file mode 120000
index b93eefc..0000000
--- a/chroot_version_hooks.d/142_unmerge_libchrome
+++ /dev/null
@@ -1 +0,0 @@
-139_unmerge_libchrome
\ No newline at end of file
diff --git a/chroot_version_hooks.d/143_rewrite_sdk_make.conf b/chroot_version_hooks.d/143_rewrite_sdk_make.conf
deleted file mode 100644
index 9721bff..0000000
--- a/chroot_version_hooks.d/143_rewrite_sdk_make.conf
+++ /dev/null
@@ -1,12 +0,0 @@
-# Copyright 2016 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We've moved around the make.conf used for Chrome OS SDK's (i.e. the internal
-# SDK used by Googlers).
-
-OLD_PATH="/mnt/host/source/src/private-overlays/chromeos-overlay/make.conf"
-NEW_PATH="/mnt/host/source/src/third_party/chromiumos-overlay/chromeos/config/make.conf.sdk-chromeos"
-if grep -qF "${OLD_PATH}" /etc/make.conf.host_setup; then
-  sudo sed -i "s:${OLD_PATH}:${NEW_PATH}:" /etc/make.conf.host_setup
-fi
diff --git a/chroot_version_hooks.d/144_nyan_to_freon b/chroot_version_hooks.d/144_nyan_to_freon
deleted file mode 100644
index 215ee84..0000000
--- a/chroot_version_hooks.d/144_nyan_to_freon
+++ /dev/null
@@ -1,22 +0,0 @@
-# Copyright 2016 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  nyan
-  nyan-big
-  nyan-kitty
-  nyan-blaze
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/145_arm_generic_to_freon b/chroot_version_hooks.d/145_arm_generic_to_freon
deleted file mode 100644
index ecc8495..0000000
--- a/chroot_version_hooks.d/145_arm_generic_to_freon
+++ /dev/null
@@ -1,19 +0,0 @@
-# Copyright 2016 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We moved a lot of files to the project-freon overlay. Make sure we
-# regen the board setup for each freon board.
-
-BOARDS=(
-  arm-generic
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    /mnt/host/source/chromite/bin/setup_board \
-      --board=${b} \
-      --skip-chroot-upgrade \
-      --regen-configs
-  fi
-done
diff --git a/chroot_version_hooks.d/146_autotest_server_logs_dir_to_symlink b/chroot_version_hooks.d/146_autotest_server_logs_dir_to_symlink
deleted file mode 100644
index 9d5c89c..0000000
--- a/chroot_version_hooks.d/146_autotest_server_logs_dir_to_symlink
+++ /dev/null
@@ -1,16 +0,0 @@
-# Copyright 2016 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# CL:422446 fixes a bug that was resulting in /build/${BOARD}/autotest/logs to
-# be a directory instead of a symlink (via chromeos-base/autotest-server
-# package).
-# But, gentoo's PMS spec doesn't allow an ebuild uprev to convert a directory to
-# symlink (https://bugs.gentoo.org/show_bug.cgi?id=326685), so we need to clean
-# up the directory manually.
-for board_root in /build/*; do
-  if [[ -d "${board_root}/autotest/logs" ]]; then
-    sudo rm -rf "${board_root}/autotest/logs"
-    sudo ln -s "/var/log/autotest" "${board_root}/autotest/logs"
-  fi
-done
diff --git a/chroot_version_hooks.d/147_x86_authpolicy_removal b/chroot_version_hooks.d/147_x86_authpolicy_removal
deleted file mode 100644
index ea98d31..0000000
--- a/chroot_version_hooks.d/147_x86_authpolicy_removal
+++ /dev/null
@@ -1,28 +0,0 @@
-# Copyright 2017 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# authpolicy got removed from x86, but incremental builds still had it and unit
-# tests failed. This script removes authpolicy from all x86 boards.
-
-BOARDS=(
-  x86-alex
-  x86-alex_he
-  x86-generic
-  x86-mario
-  x86-zgb
-  x86-zgb_he
-)
-
-packages=(
-  chromeos-base/authpolicy
-)
-
-for b in "${BOARDS[@]}"; do
-  if [[ -d /build/${b} ]]; then
-    if ROOT="/build/${b}" qlist -ICe "${packages[@]}" >&/dev/null; then
-      info "Cleaning ${packages[*]} from /build/${b}"
-      sudo ROOT="/build/${b}" qmerge -yqU "${packages[@]}"
-    fi
-  fi
-done
diff --git a/chroot_version_hooks.d/148_remove_eselect_bashcomp b/chroot_version_hooks.d/148_remove_eselect_bashcomp
deleted file mode 100644
index 8cb0503..0000000
--- a/chroot_version_hooks.d/148_remove_eselect_bashcomp
+++ /dev/null
@@ -1,9 +0,0 @@
-# Copyright 2017 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# CL:503619 removed app-admin/eselect-bashcomp in preparation for upgrading
-# app-shells/bash-completion, but the existing chroot may still it. This script
-# removes eselect-bashcomp from the chroot.
-
-sudo qmerge -yqU 'app-admin/eselect-bashcomp'
diff --git a/chroot_version_hooks.d/149_icedtea_upgrade b/chroot_version_hooks.d/149_icedtea_upgrade
deleted file mode 100644
index ed7bdbb..0000000
--- a/chroot_version_hooks.d/149_icedtea_upgrade
+++ /dev/null
@@ -1,11 +0,0 @@
-# Copyright 2017 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Upgrade the icedtea installation from Java 7 to Java 8.
-
-sudo qmerge -yqU dev-java/icedtea-bin:7
-# If no java versions are installed, this will fail.  When we update the SDK
-# though, it'll pull in Java 8, and the ebuild should select that version
-# automatically for us.
-sudo java-config --set-system-vm 1 || true
diff --git a/chroot_version_hooks.d/150_move_eselect_python b/chroot_version_hooks.d/150_move_eselect_python
deleted file mode 100644
index 9966113..0000000
--- a/chroot_version_hooks.d/150_move_eselect_python
+++ /dev/null
@@ -1,11 +0,0 @@
-# Copyright 2017 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# CL:574040 and CL:573885 moved app-admin/eselect-python to
-# app-eselect/eselect-python in preparation to updating to newer python:2.7,
-# python:3.3 and python-exec.
-# Update python 2.7 and 3.3 to force rebuild of eselect-python which will
-# also remove the old app-admin/eselect-python.
-
-sudo emerge -uNv --quiet python:2.7 python:3.3
diff --git a/chroot_version_hooks.d/151_clean_i686_go b/chroot_version_hooks.d/151_clean_i686_go
deleted file mode 100644
index 35ecbdb..0000000
--- a/chroot_version_hooks.d/151_clean_i686_go
+++ /dev/null
@@ -1,13 +0,0 @@
-# Copyright 2017 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# We've dropped i686 go support, so clean out any old installs to avoid
-# constantly detecting updates are necessary.
-# https://chromium-review.googlesource.com/444042
-sudo qmerge -yqU cross-i686-pc-linux-gnu/go
-
-# Purge the crossdev cache since it records i686/go settings.
-# This will cause update_chroot to re-run once, but should be fine as it'll
-# utilize binpkgs.
-sudo rm -f /usr/local/portage/crossdev/.configured.json
diff --git a/chroot_version_hooks.d/152_rewrite_sudoers.d b/chroot_version_hooks.d/152_rewrite_sudoers.d
deleted file mode 120000
index c4ab18d..0000000
--- a/chroot_version_hooks.d/152_rewrite_sudoers.d
+++ /dev/null
@@ -1 +0,0 @@
-153_rewrite_sudoers.d
\ No newline at end of file
diff --git a/chroot_version_hooks.d/153_rewrite_sudoers.d b/chroot_version_hooks.d/153_rewrite_sudoers.d
deleted file mode 100644
index 2a11b7a..0000000
--- a/chroot_version_hooks.d/153_rewrite_sudoers.d
+++ /dev/null
@@ -1,53 +0,0 @@
-# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Note that this script is invoked by make_chroot in addition
-# to normal upgrade pathways.
-
-set -e
-
-if [ "${UID:-$(id -u)}" != 0 ]; then
-  # Note that since we're screwing w/ sudo variables, this script
-  # explicitly bounces up to root for everything it does- that way
-  # if anyone introduces a temp depriving in the sudo setup, it can't break
-  # mid upgrade.
-
-  . "$(dirname "$(dirname "$0")")/common.sh" || exit 1
-
-  load_environment_whitelist
-  exec sudo bash "$0" / "${USER}" "${ENVIRONMENT_WHITELIST[@]}"
-  exit 1
-fi
-
-# Reaching here means we're root.
-
-if [ $# -lt 2 ]; then
-  echo "Invoked with wrong number of args; expected root USER [variables]*"
-  exit 1
-fi
-
-root=$1
-username=$2
-shift
-shift
-set -- "${@}" CROS_WORKON_SRCROOT PORTAGE_USERNAME
-
-cat > "${root}/etc/sudoers.d/90_cros" <<EOF
-Defaults env_keep += "${*}"
-
-# We need adm currently to let sudo work inside ebuilds.
-%adm ALL=(ALL) ALL
-root ALL=(ALL) ALL
-${username} ALL=NOPASSWD: ALL
-
-# Simplify the -v option checks due to overlap of the adm group and the user's
-# supplementary groups.  We don't set any passwords, so disable asking.
-# https://crbug.com/762445
-Defaults verifypw = any
-EOF
-
-chmod 0440 "${root}/etc/sudoers.d/90_cros"
-chown root:root "${root}/etc/sudoers.d/90_cros"
-
-exit 0
diff --git a/chroot_version_hooks.d/154_clean_sdk_post_libcxx b/chroot_version_hooks.d/154_clean_sdk_post_libcxx
deleted file mode 100644
index 256f8bd..0000000
--- a/chroot_version_hooks.d/154_clean_sdk_post_libcxx
+++ /dev/null
@@ -1,43 +0,0 @@
-# Copyright 2018 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Rebuild host packages after libc++ migration.
-
-REPOS=( $(portageq envvar PORTDIR) $(portageq envvar PORTDIR_OVERLAY) )
-
-package_exists() {
-  local pkg=$1
-  for repo in "${REPOS[@]}"; do
-    [[ -d "${repo}/${pkg}" ]] && return 0
-  done
-  return 1
-}
-
-# Find packages that use libstdc++ and remove their existing
-# binary package.
-PKGS=( $(qdepends -qCN -k NEEDED -Q 'libstdc\+\+\.so\.6') )
-PKGDIR=$(portageq envvar PKGDIR)
-PKGS_TO_REMOVE=()
-cd "${PKGDIR}"
-for pkg in "${PKGS[@]}"; do
-  sudo rm -f "${pkg}-"[0-9]*.tbz2
-  # Collect packages without ebuilds.
-  if ! package_exists "${pkg}"; then
-    PKGS_TO_REMOVE+=( "${pkg}" )
-  fi
-done
-
-# Remove packages no longer present in tree.
-if [[ ${#PKGS_TO_REMOVE[@]} -ne 0 ]]; then
-  echo "Removing non-existent tree packages ${PKGS_TO_REMOVE[*]}"
-  sudo qmerge -Uqy "${PKGS_TO_REMOVE[@]}"
-fi
-
-# New list that can be passed to portage.
-# Ensure that llvm and clang are always pulled in.
-PKGS=( sys-devel/llvm sys-devel/clang )
-PKGS+=( $(qdepends -qCN -k NEEDED -Q 'libstdc\+\+\.so\.6') )
-
-# Reinstall the packages using fresh binary packages.
-sudo emerge --getbinpkg "${PKGS[@]}"
diff --git a/chroot_version_hooks.d/155_clean_boards_post_libcxx b/chroot_version_hooks.d/155_clean_boards_post_libcxx
deleted file mode 100644
index a51a8b6..0000000
--- a/chroot_version_hooks.d/155_clean_boards_post_libcxx
+++ /dev/null
@@ -1,39 +0,0 @@
-# Copyright 2018 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Clean board packages after libc++ migration.
-for board_root in /build/* ; do
-  board=${board_root##*/}
-  [[ "${board}" == "bin" ]] && continue
-  # Clean local portage caches. This is necessary if
-  # there are cros_workon packages.
-  sudo rm -rf ${board_root}/var/cache/portage/*
-
-  # Find packages using libstdc++.
-  PKGS=( $(qdepends-${board} -qCN -k NEEDED -Q 'libstdc\+\+\.so\.6') )
-  if [[ ${#PKGS[@]} -eq 0 ]]; then
-    continue
-  fi
-  echo "Cleaning packages using libstdc++ from ${board}"
-  # Collect list of packages to remove excluding gcc-libs and binutils.
-  PKG_TO_REMOVE=()
-  for pkg in "${PKGS[@]}"; do
-    if [[ "${pkg}" != "sys-libs/gcc-libs" && "${pkg}" != "sys-devel/binutils" ]]; then
-      PKG_TO_REMOVE+=( "${pkg}" )
-    fi
-  done
-
-  if [[ ${#PKG_TO_REMOVE[@]} -eq 0 ]]; then
-    continue
-  fi
-
-  PKGDIR=$(portageq-${board} envvar PKGDIR)
-  cd "${PKGDIR}"
-  # Remove existing binary packages.
-  for pkg in "${PKG_TO_REMOVE[@]}"; do
-    sudo rm -f "${pkg}"-[0-9]*.tbz2
-  done
-  # Unmerge all packages using libstdc++.
-  qmerge-${board} -Uqy "${PKG_TO_REMOVE[@]}"
-done
diff --git a/chroot_version_hooks.d/156_clean_arm_python_lib64 b/chroot_version_hooks.d/156_clean_arm_python_lib64
deleted file mode 100644
index f0dff24..0000000
--- a/chroot_version_hooks.d/156_clean_arm_python_lib64
+++ /dev/null
@@ -1,29 +0,0 @@
-# Copyright 2018 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Many python packages were poisoned with lib64 paths.  Clear them.
-# https://crbug.com/876634
-
-clear_board() {
-  local b="$1" board="$2"
-
-  if [[ "$(portageq-${board} envvar ARCH 2>/dev/null)" != "arm" ]]; then
-    return
-  fi
-
-  echo "Cleaning out board ${board}"
-  local pkgs=( $(qfile --root "${b}" -Cq /usr/lib64) )
-  if [[ ${#pkgs[@]} -gt 0 ]]; then
-    sudo qmerge --root "${b}" -Uqy "${pkgs[@]}"
-  fi
-  sudo rm -rf "${b}/usr/lib64"
-}
-
-for b in /build/*; do
-  if [[ -d "${b}/usr/lib64" ]]; then
-    board="${b##*/}"
-    clear_board "${b}" "${board}" &
-  fi
-done
-wait
diff --git a/chroot_version_hooks.d/157_unmerge_libunwind b/chroot_version_hooks.d/157_unmerge_libunwind
deleted file mode 100644
index c77fa6f..0000000
--- a/chroot_version_hooks.d/157_unmerge_libunwind
+++ /dev/null
@@ -1,8 +0,0 @@
-# Copyright 2018 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# sys-libs/libunwind got replaced by sys-libs/llvm-libunwind, so clean out the
-# old one. Eat errors if the package has already been unmerged.
-
-sudo qmerge -Uqy sys-libs/libunwind || true
diff --git a/chroot_version_hooks.d/158_glibc_update b/chroot_version_hooks.d/158_glibc_update
deleted file mode 100644
index 04bed8a..0000000
--- a/chroot_version_hooks.d/158_glibc_update
+++ /dev/null
@@ -1,9 +0,0 @@
-# Copyright 2018 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Manually force sys-libs/glibc to be upgraded to the new version when updating.
-# net-libs/rpcsvc-proto is needed to avoid portage complains.
-if portageq has_version / '<sys-libs/glibc-2.27'; then
-  sudo emerge -1ug '>=sys-libs/glibc-2.27' 'net-libs/rpcsvc-proto'
-fi
diff --git a/chroot_version_hooks.d/159_glibc_headers b/chroot_version_hooks.d/159_glibc_headers
deleted file mode 100644
index d1cc6d8..0000000
--- a/chroot_version_hooks.d/159_glibc_headers
+++ /dev/null
@@ -1,47 +0,0 @@
-# Copyright 2018 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Manually prune headers that glibc no longer provides.  This is a bit hacky
-# since our manually deployed glibc tarball doesn't track contents anywhere.
-#
-# This only applies to board sysroots where we manually inject headers.  The
-# SDK upgrades glibc like a proper package and thus keeps track for us.
-
-update() {
-  local root=$1 board=$2
-
-  # We know these header files have been punted, so forcibly delete them.
-  sudo rm -f \
-    "${root}/usr/include/xlocale.h" \
-    "${root}/usr/include/sys/ultrasound.h"
-
-  # The RPC headers have moved from glibc to a dedicated package.  If that
-  # package has been installed and replaced the headers, we don't want to
-  # delete them.  But if they're still orphaned, prune them.
-  #
-  # We send the output of find to /dev/null in case the rpc dirs have already
-  # been cleaned up (due to a fresh glibc-2.27-only install).
-  local files=() file
-  while read file; do
-    # Newer glibc has one file it still wants to keep, so filter it out.
-    if [[ "${file}" == */rpc/netdb.h ]]; then
-      continue
-    fi
-
-    files+=( "${file}" )
-  done < <(find "${root}"/usr/include/rpc* -type f \
-             -exec qfile-${board} -Ro {} + 2>/dev/null)
-  sudo rm -f "${files[@]}"
-
-  # If the dirs are empty, trim them.  But don't force it in case other packages
-  # have installed real files in there.
-  sudo rmdir "${root}"/usr/include/rpc* 2>/dev/null || :
-}
-
-for board_root in /build/*; do
-  board=${board_root##*/}
-  update "${board_root}" "${board}" &
-done
-
-wait
diff --git a/chroot_version_hooks.d/160_portage_upgrade b/chroot_version_hooks.d/160_portage_upgrade
deleted file mode 100644
index a040cd7..0000000
--- a/chroot_version_hooks.d/160_portage_upgrade
+++ /dev/null
@@ -1,16 +0,0 @@
-# Copyright 2018 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# When portage upgrades in place, it sometimes mixes old & new versions of
-# the python modules.  So the old APIs might be used with new callers who
-# try to pass args it doesn't expect.  We can workaround this by upgrading
-# twice -- the first will fail partially, but the second makes it through.
-
-if qlist -Iq '<portage-2.3' >/dev/null; then
-  echo "Trying upgrade of portage"
-  if ! sudo emerge -qug '>portage-2.3'; then
-    echo "Retrying upgrade"
-    sudo emerge -qug '>portage-2.3'
-  fi
-fi
diff --git a/chroot_version_hooks.d/166_gtest_upgrade b/chroot_version_hooks.d/166_gtest_upgrade
deleted file mode 120000
index 2a8c569..0000000
--- a/chroot_version_hooks.d/166_gtest_upgrade
+++ /dev/null
@@ -1 +0,0 @@
-134_clean_portage_cache
\ No newline at end of file
diff --git a/chroot_version_hooks.d/134_clean_portage_cache b/chroot_version_hooks.d/166_gtest_upgrade
similarity index 100%
rename from chroot_version_hooks.d/134_clean_portage_cache
rename to chroot_version_hooks.d/166_gtest_upgrade