am 461af5c8: am 7ab900ed: Merge change Ic8093c11 into eclair

Merge commit '461af5c8db02ecbf81b0e57934f86a7ab6c4e8b6' into eclair-mr2-plus-aosp

* commit '461af5c8db02ecbf81b0e57934f86a7ab6c4e8b6':
  Hold a lock while we access the preview heap.