Merge "Don't launch placeholder for bottom TaskFragment when waiting for top"...

Merge "Don't launch placeholder for bottom TaskFragment when waiting for top" into tm-dev am: d4011e0e

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17983784



Change-Id: I89058545c010c4683518b623130ebf96e525f121
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>