Merge "Make footer button tap target 48dp tall" into sc-qpr1-dev am: be7e7e2d63 am: 317613f83b am: ee0b6e83db

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

Change-Id: I0b9533911b0eb75fdc7ec9fda37369da6824b36e