am a9c83f5c: Make sure the arena cache cannot be reused.
am a9c83f5c: Make sure the arena cache cannot be reused.

* commit 'a9c83f5c9c1af9a5298f4bb96fb5de83f6da2828':
  Make sure the arena cache cannot be reused.

AndroidExternal/jemalloc,AndroidExternal/jemalloc,AndroidExternal/jemalloc,AndroidExternal/jemalloc