Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278032 0039d316-1c4b-4281-b951-d872f2087c98

.DEPS.git

@@ -9,7 +9,7 @@ vars = {
     'git_url':
          'https://chromium.googlesource.com',
     'webkit_rev':
-         '@639644e03484d626291dbef0bb792b80cbdefc36',
+         '@a6814bfa9ae33515295aa137b2ea8aead2a2cb31',
     'angle_revision':
          'afeeda9391c1f3fc0c35c04fbc448480177059d8'
 }