Merge "Constraint Snackbar's width to 504dp" into sc-v2-dev am: 3013c7ecf5

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/16388221

Change-Id: I7067c281f20b405f47253a486275189f63b6b5d9