Merge "Add config option to add extra cfg flags." into main am: 1358b287fe

Original change: https://android-review.googlesource.com/c/platform/development/+/2843096

Change-Id: I7d4f44152d121fa921c9acdff465123b03d1bc6b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>