Merge "Add a new test target for rollback observer." into main am: fe68c630

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2980871



Change-Id: Ifacc8c2cea247224e1239b7bd780e7f1dfe2f479
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>