Merge "Add the "enable emsg" flag" into rvc-dev am: 73113a6997 am: 31a63169a5 am: e71253ad4f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11986788

Change-Id: I5ad531724dd83acf95eae0be72f7402d87a619a7