Merge "Call onBackCancelled() when an active callback is removed from the...

Merge "Call onBackCancelled() when an active callback is removed from the WindowOnBackInvokedDispatcher" into udc-dev am: 3c0dd66b am: 8937b6c3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23103198



Change-Id: Iadaf4b0f2bfdfb32369f5e9b6ec5c17db8d97eb9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>