Merge "Merge "MediaRouter2: Sync routes when first RouteCallback is...

Merge "Merge "MediaRouter2: Sync routes when first RouteCallback is registered" into rvc-dev am: ebb7ae66 am: 813d77ae am: ed1f83f8" into rvc-qpr-dev-plus-aosp am: d61e677f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11733427

Change-Id: I13919f35eecc30265257c4fc9c2b1f1cf4971948