Merge "[pm/metrics] add loadingCompletedTime in stats" into udc-dev am: aede9255

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21893930



Change-Id: Ic0dcc04a8c23cb068535c981e696fa807d92b7b3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>