Merge "Renamin TaskbarContainerView to TaskbarDragLayer" into sc-dev am: 2f0595e76e

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/14680570

Change-Id: Ic3aa579ebc2df7b3053f8df14bceebea0e2850aa