Merge "Fix crash when trying to get bar transitions before nav bar is created"...

Merge "Fix crash when trying to get bar transitions before nav bar is created" into sc-dev am: 66072f6b

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/13887848

Change-Id: If9d9d5092a783f1fba03460e9e04c97ba3f94528