Merge "Cache window and icon color of splash screen starting window" into sc-dev am: 00d26d71 am: de4577a2 am: 1c992435

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14842877

Change-Id: Id41d20828253263631eaf886f0a692c4b19e3b5a