Merge "Wait for taskbar to become visible after closing launcher in tests"...

Merge "Wait for taskbar to become visible after closing launcher in tests" into sc-v2-dev am: 17e9b51e am: c8ec2888

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/15301470

Change-Id: Ib7dbd2b47dc87e3bbe888af71c7727ca6f6ae3e0