Merge "Remove dismiss target only when it's attached to a parent." into tm-qpr-dev am: 489880bc

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21525766



Change-Id: I371feb8ebab492e909fa7dc8e7604244e8d62064
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>