API: Suppress existing NullableCollections lints am: 6a6aa5e23d am: 4da67dd2f6 am: 98eb82a6d3

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1566096

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I314b97d2677f26b0a9c09a52918df49096450aea