Merge changes from topic "nullablecollection" am: d667ef7737

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1567165

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I754de2bd3b24e9027d6cf9776ea93e611a8e42c7
tree: 2e48d31cf7a87d9c5c302ccb94d495ba86c6048d
  1. framework/
  2. service/
  3. OWNERS