Refactor Folder to use ActivityContext and BaseDragLayer am: 1906cc33f9

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/13555111

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I958d909d7dc2ed6c02d0517da217a1b810eb3133