[automerger skipped] build_flag: improve default flag value directory am: 784925ff -s ours

am skip reason: Merged-In Ida1f906b75704f658e7fa1de703e0c789dce06a6 with SHA-1 d6406171 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/build/soong/+/27252351



Change-Id: I3208cb2f161ecaa2af40d98fcd221a06a846c751
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>