make_chroot: improve early logging a bit

Add some basic command logging to every command we run inside the
chroot.  This helps debug early bootstrap failures without adding
too much noise to the process.

BUG=chromium:906289
TEST=sdk bootstrap still works

Change-Id: Ibffeca33c2a42806255335ce89f778225a99db9e
Reviewed-on: https://chromium-review.googlesource.com/1387716
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Alex Klein <saklein@chromium.org>
diff --git a/sdk_lib/make_chroot.sh b/sdk_lib/make_chroot.sh
index a2edead..22f8608 100755
--- a/sdk_lib/make_chroot.sh
+++ b/sdk_lib/make_chroot.sh
@@ -91,6 +91,7 @@
 
 # Invoke enter_chroot.  This can only be used after sudo has been installed.
 enter_chroot() {
+  echo "[enter_chroot] $*"
   "$ENTER_CHROOT" --cache_dir "${FLAGS_cache_dir}" --chroot "$FLAGS_chroot" \
     -- "${ENTER_CHROOT_ARGS[@]}" "$@"
 }
@@ -99,6 +100,7 @@
 # This should be used prior to sudo being merged.
 early_env=()
 early_enter_chroot() {
+  echo "[early_enter_chroot] $*"
   "$ENTER_CHROOT" --chroot "$FLAGS_chroot" --early_make_chroot \
     --cache_dir "${FLAGS_cache_dir}" \
     -- "${ENTER_CHROOT_ARGS[@]}" "${early_env[@]}" "$@"