[automerger skipped] [DO NOT MERGE] Improve brightness handling during screen off timeout. am: bb8219d84b -s ours

am skip reason: skipped by user tsuji

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15974634

Change-Id: I127378c325d2cc17938c5fb073f8220f843749e6