Merge "Add game mode to TimeStats - System Server changes" into sc-dev am: 5c518a08 am: 8870297a am: 85ae88dc

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14842920

Change-Id: Ifc96ea52d92420f4e673d7c890f7571752f2b945