Merge "Use ArraySet#add() instead of ArraySet#append()" am: 627c6a5258 am: ee5644f6b5

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

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I4418327b7201e31620a71b693a70403889a25fbf