Merge "aconfig: consolidate how fully qualified flag name is calculated" into main am: 5f24a209

Original change: https://android-review.googlesource.com/c/platform/build/+/2864525



Change-Id: I8d4bfa54fada04c011a0d08455a751cf88d1f1ed
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>