Merge "[sysui] Use weak reference for the listener in...

Merge "[sysui] Use weak reference for the listener in NavigationBarTransitions" into tm-qpr-dev am: 5af264c1 am: 95881937 am: c49dd23a

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21931839



Change-Id: I940f0d41fdb18d356dcc7353af6f2c474724a6db
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>