GitLab

TransportDIB handles are file descriptors on mac, which are duped when sent over IPC. Hence, they change their value, and the handle that comes back over IPC is not the same that was originally sent -- so they can't be used as map keys.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/3037006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@52925 0039d316-1c4b-4281-b951-d872f2087c98