storageproxy: Support POST_COMMIT sync for all commands am: 5b02ed521c

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/19517836

Change-Id: I3aeeb035f1168bd2c9bdbba43ddd014c92d8a8c9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>