Fix crash/flicker with taskbar when canceling drag and drop am: 729eb8458b am: 0cb7c659b3

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/17776925

Change-Id: Ida1ee71762e25c7b09dd9ff6837a4ad8aea4ab15
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>