Merge "aconfig_proto: add doc in aconfig.proto file" into main am: b7d4bedd

Original change: https://android-review.googlesource.com/c/platform/build/+/2945156



Change-Id: I8d54529a0f690738a32de9d47806b5aaf1e2f0f6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>