Merge "Expand @FlaggedApi(Flags.FLAG) in *all* API signature files" into main am: 0c787f5b6e am: 4f3dc01ec1 am: 3045dc0633

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2765045

Change-Id: Ib8e506d0c7e011f2ee85096464f83ffd22672f0e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>