Merge "Wait for ACTION_MEDIA_MOUNTED before removing started users." into tm-dev am: f171d00972

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18619746

Change-Id: Id9eada5dbe98fa3f6ec0e4ca977986a85167761d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>