[automerger] Rework thumbnail cleanup am: 82a2a87474 am: 97eb9d056a skipped: cb9dd5d0e6 am: ddfcb07714  -s ours am: 7e7681f7c3  -s ours am: 36f77be954  -s ours am: 661ab62146  -s ours
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Change-Id: Ie69c0624ca8bdf5bd13a0b03588aae4079d27e64