Revert 65558 - roll to ffmpeg fix for llvm

BUG=61931
TEST=none

Review URL: http://codereview.chromium.org/4752001

TBR=fbarchard@chromium.org
Review URL: http://codereview.chromium.org/4637003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@65559 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -11,7 +11,7 @@ vars = {
   "nacl_revision": "3626",
   "libjingle_revision": "33",
   "libvpx_revision": "65287",
-  "ffmpeg_revision": "65557",
+  "ffmpeg_revision": "65312",
 }
 
 deps = {