minor cleanup in wav/vorbis patches

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/6178007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@70986 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -11,7 +11,7 @@ vars = {
   "nacl_revision": "4085",
   "libjingle_revision": "50",
   "libvpx_revision": "65287",
-  "ffmpeg_revision": "70905",
+  "ffmpeg_revision": "70984",
 }
 
 deps = {