It's old, unneeded, and poorly tested.
Created attachment 257709 [details] Patch
It's also the only thing that requires the June 2010 DirectX SDK as opposed to the one that comes with VS2012.
Comment on attachment 257709 [details] Patch r=me
*** Bug 146459 has been marked as a duplicate of this bug. ***
Committed in r187602. <http://trac.webkit.org/changeset/187602>