Merge "Run LowpanManager on BackgroundThread" am: e9c000eee2 am: f4e6668082 am: eb32604c2b

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1513142

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Ica052872b3fa68321d93be37969387c9f3f71497