Merge "Add placeholder when media control title is blank" into tm-dev am: dfc4955c

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23502366



Change-Id: Iac03e87246274a0f04ce12b60891e6b2f048c63e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>