Merge "Adapt transition merge during recents into onTaskAppeared." into sc-dev am: aadebf0a am: 772bb525 am: d1b2c200

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14297820

Change-Id: I6e72d8c9a04c40c6da454891b1ba4c8f9f0093c5