Merge "Implement light mode for persistent Taskbar." into tm-qpr-dev am: 2790c9db

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/21592661



Change-Id: Idbf2609daac8c6e35c9edae08e05b379eae80a0c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>