Merge "Remove the default impl of setTriggerBack" into tm-qpr-dev am: 59b7cd4e am: 62b62386

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20131821



Change-Id: If5799820d5617246f46b0e62f61ef86090c89b66
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>