Merge "Actually trigger back action on Back Arrow fling" into tm-qpr-dev am: 6c11adfa

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19484845



Change-Id: I45229c89d7397f3eda033d296b040bc434b0bfd8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>