build_packages.sh: Add --chrome argument.

Add --chrome as an alias for --internal --nouse_any_chrome.

BUG=b:183741031
TEST=build_packages --board eve --chrome --pretend works

Change-Id: Id71c4b1888a70d049e7ff56d1e0f45392e781ec4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/3445294
Tested-by: Alex Klein <saklein@chromium.org>
Auto-Submit: Alex Klein <saklein@chromium.org>
Reviewed-by: Cindy Lin <xcl@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Alex Klein <saklein@chromium.org>
diff --git a/build_packages.sh b/build_packages.sh
index 82843e9..6cd8c77 100644
--- a/build_packages.sh
+++ b/build_packages.sh
@@ -25,6 +25,8 @@
 # Developer-visible flags.
 DEFINE_string board "${DEFAULT_BOARD}" \
   "The board to build packages for."
+DEFINE_boolean chrome "${FLAGS_FALSE}" \
+  "Ensure chrome instead of chromium. Alias for --internal --nouse_any_chrome."
 DEFINE_boolean usepkg "${FLAGS_TRUE}" \
   "Use binary packages to bootstrap when possible."
 DEFINE_boolean usepkgonly "${FLAGS_FALSE}" \
@@ -153,6 +155,12 @@
   "chromeos-base/chrome-icu"
 )
 
+# Alias/implied flag translations.
+if [[ "${FLAGS_chrome}" -eq "${FLAGS_TRUE}" ]]; then
+  FLAGS_internal="${FLAGS_TRUE}"
+  FLAGS_use_any_chrome="${FLAGS_FALSE}"
+fi
+
 if [[ "${FLAGS_internal}" -eq "${FLAGS_TRUE}" ]]; then
   export USE="${USE} chrome_internal"
 fi