Merge "Fix grid selection be cleared if rotate screen at multi-pane device" into sc-v2-dev am: 2e4c0a100d am: dab596e952

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/ThemePicker/+/16245006

Change-Id: I04aa7abf6d496950ec1d32e49d5418da6328ec22