Merge "Add RootTargetPreparer for explicitly specifying the root dependency" into main am: 40673c5711

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2961299

Change-Id: If84fa71150b819f79c096505f295eadbfa7c0337
Signed-off-by: Automerger Merge Worker <[email protected]>