Merge "Add RootTargetPreparer for explicitly specifying the root dependency" into main am: 5613fb78ee

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2963562

Change-Id: Id2a5c535854e3ba45cf333b23482642ceb893b2e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>