Merge "IME animation: hide IME-related navbar icons until perceptible" into rvc-dev am: e658c76b5c am: f771bf5301 am: c46149e5ee am: ffdf41af4d

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11837615

Change-Id: I3aafbd212ec158a05ace1d5c24b17050187f9772