Merge "Revert "Prevent setting mIsStashed in TaskbarStashController"" into udc-qpr-dev am: 12cd6076d3

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/24447385

Change-Id: I9719eb5349bc4a0cbbfde7383c11d3b56d5f4077
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>