Merge "aconfig: explicitly @hide FLAG_ constants" into main am: 65d19d14 am: 7fca45d3

Original change: https://android-review.googlesource.com/c/platform/build/+/2748397



Change-Id: I56f2e3632629536681055410407a815ff9d12c59
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>