Merge "Add MediaRouterManager.Callback#onSessionReleased" into rvc-dev am: 2950ebf07d am: b18e625b5b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11733425

Change-Id: I15c6f262793271eacf41ec3e475dad0e3c29b385