cros_mark_as_stable: Expose the git commit message for use in other scripts.

This way other scripts can find the stable uprev CLs in a reliable way.

TEST=ran the cros_mark_as_stable unittests.

Change-Id: I23bda2cad664f23e1ab3177ac8fd6ceba35e23d4
Reviewed-by: Mike Frysinger <>
Commit-Queue: Gabe Black <>
Tested-by: Gabe Black <>
diff --git a/scripts/ b/scripts/
index 2d5db92..9f66450 100644
--- a/scripts/
+++ b/scripts/
@@ -17,6 +17,8 @@
 from chromite.lib import parallel
 from chromite.lib import portage_util
+# Commit message subject for uprevving Portage packages.
+GIT_COMMIT_SUBJECT = 'Marking set of ebuilds as stable'
 # Commit message for uprevving Portage packages.
 _GIT_COMMIT_MESSAGE = 'Marking 9999 ebuild for %s as stable.'
@@ -162,7 +164,7 @@
   description = git.RunGit(cwd,
       ['log', '--format=format:%s%n%n%b', '%s..%s' % (
        push_branch, stable_branch)]).output
-  description = 'Marking set of ebuilds as stable\n\n%s' % description
+  description = '%s\n\n%s' % (GIT_COMMIT_SUBJECT, description)
   cros_build_lib.Info('For %s, using description %s', cwd, description)
   git.CreatePushBranch(constants.MERGE_BRANCH, cwd)
   git.RunGit(cwd, ['merge', '--squash', stable_branch])