Merge "Ensure the back gesture window is not touchable" into sc-dev am:...

Merge "Ensure the back gesture window is not touchable" into sc-dev am: 4c0f4e3a am: 51714873 am: 5e872b94

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14926475

Change-Id: I74ec5457900a3d3831216ab2b7a75027276d1546