Merge "Make footer button tap target 48dp tall" into sc-qpr1-dev am: be7e7e2d63 am: 317613f83b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15854192

Change-Id: Ic1cde1e98f714d70a70559f90a8c46f0b3444e14