Merge "aconfig: use an enum to represetn flag type" into main am: cd381f5d64

Original change: https://android-review.googlesource.com/c/platform/build/+/3020146

Change-Id: I52215a57d0f04807d71cd39cf40e861a98db1ab8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>