Merge "Adding support for easily extending Launcher DragAndDrop support" into tm-dev am: d7281d09

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/18287509



Change-Id: I4789afed519610d4a079bb2c241e0295210d541b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>