[automerger] DO NOT MERGE Rework thumbnail cleanup am: b514ce9b38 am: b8dad6c644 am: 019eec3923 skipped: 9d13b0f6ca am: 4ef2cbc58d am: 31ee079d5f am: 6100f6d3b2

Change-Id: I6388ec63ab6d29d1b002cc296571e67278245fc0