Scrims should be grey when in-app

Bug: 38164389
Test: runtest -x colorextraction/tests/src/com/google/android/colorextraction/ColorExtractorTest.java
Test: runtest -x tests/src/com/android/systemui/colorextraction/SysuiColorExtractorTests.java
Change-Id: Ifcc04a8562e46b4f65bce0470ccd6c02dffcf377
16 files changed