Merge "Define flag for wallpaper preview loading animation (2/3)" into udc-qpr-dev am: c0f9ab57

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24042327



Change-Id: I55e25baa9fd8884611b2bbb717b5b8f7f75656a2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>