Merge "Add system staging dir stamp file for bazel sandwich" into main am:...

Merge "Add system staging dir stamp file for bazel sandwich" into main am: e88ddaec am: f0ebc2f6

Original change: https://android-review.googlesource.com/c/platform/build/+/2651320



Change-Id: Ie6b8c7a7f4cd894676a84ae3049ca5696868dc20
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>