Merge "Write stats when background dexopt job is ended." into tm-dev am: 303df2f8

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18185146



Change-Id: I030f76f7f56c7c81d37f3186fd0173153fa98f0e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>