API: Suppress existing NullableCollections lints am: 515b26ae98 am: b59b4d91dc am: 98eb82a6d3

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

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I314b97d2677f26b0a9c09a52918df49096450aea
tree: 7b946c1d8dcd6d571b2d04e1a482871f328e019c
  1. framework/
  2. service/
  3. OWNERS