[automerger skipped] [DO NOT MERGE] Improve brightness handling during screen off timeout. am: bb8219d84b -s ours am: 4cf6d3eee8 -s ours

am skip reason: skipped by user tsuji

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

Change-Id: I9c7a28ffa01c3f815a97a726f84b8d52cd2cc4dd