[DO NOT MERGE] Fix DozeScreenBrightnessTest. am: 20d85a91d4 am: cb17c9d93c

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15994907

Change-Id: I8c3fd1d79d9a4fd9f74e368e7d707372d1f97fee