Merge "Use ArraySet#add() instead of ArraySet#append()" am: 55793cc0cb am: 8d07cea94a am: 9691a4a867

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1615181

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Ic1cbcbb6f9dc83e664593b8e095a0f9b80697b83