Merge "MediaMetrics: Prepare statistics for protos" into rvc-dev am: 09869a1c36 am: 7100301e34

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/11455384

Change-Id: I8ca3224cc1bb4b70bfe0d30dc7ee1790018e5cf4