Merge "Provide config for customize the showing strategy of back target." into...

Merge "Provide config for customize the showing strategy of back target." into udc-dev am: b11b27d4

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21578380



Change-Id: Ib7bd748d662da26df90b9f0393998f5195de1e05
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>