Merge "Fix customized activity open/close animation backdrop color" into tm-qpr-dev am: 53c5aa67

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20662608



Change-Id: I741fe83ed27a928751607d232de94cd4857f010b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>