Merge "Center drop target button alignment across devices" into tm-dev am: 179c289a6c am: 7ca1b38d7e

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/18580267

Change-Id: I57dd855387257a8704f8529f14ea176562e63549
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>