Merge "Update nav bar buttons to spec." into tm-qpr-dev am: fc8606dadc am: 3d8a020ab5

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/22211900

Change-Id: I73bb947b384f251adf6934d31c0f29eb2b1a4a83
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>