Roll libvpx to fix build breaks

Some libvpx files are marked with executable bit.
TBR=vandebo

BUG=None
TEST=None

Review URL: http://codereview.chromium.org/8390007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@107147 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -27,7 +27,7 @@ vars = {
   "nacl_toolchain_revision": "6757",
 
   "libjingle_revision": "88",
-  "libvpx_revision": "107120",
+  "libvpx_revision": "107145",
   "ffmpeg_revision": "106016",
   "sfntly_revision": "98",
   "skia_revision": "2515",