Merge "Rotate back button drawable when IME present." into tm-qpr-dev am: 71a7a13f06

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/21136523

Change-Id: I7028686e031f8182953ee0b6981db34a8e6933cd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>