Merge "Add non null check on mViewPager" into tm-dev am: 6c2c619d35 am: 199c5e129b

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/18349770

Change-Id: Ie1957eaab6107597dad4c1080a519d6535bdaa74
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>