Some comments suggest that we can make a cleaner implementation that doesn't requiring opening files in /tmp.
"""
  // Q: Why not use the shm_open() etc. APIs?
  // A: Because they're limited to 4mb on OS X.  FFFFFFFUUUUUUUUUUU
"""

"""
      // We could imagine re-opening the file from /dev/fd, but that can't make
      // it readonly on Mac: https://codereview.chromium.org/27265002/#msg10
"""

This was prompted from an offline discussion with jennyz@ regarding https://bugs.chromium.org/p/chromium/issues/detail?id=602515.
"""
The call stack seem showing the problem might not be chromeos specific, looks like some shared memory files are created during the play, but not cleaned up, so it filled up the /tmp disk and oom killed chrome.
"""