Make sure <url>s are being serialized according to spec

third_party/WebKit/LayoutTests/animations/interpolation/resources/interpolation-test.js

 /*
  * Copyright (C) 2015 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 192 matching lines @@
               replace(/\.$/, '').
               replace(/^-0$/, '0');
         });
   }
 
   var anchor = document.createElement('a');
   function sanitizeUrls(value) {
     var matches = value.match(/url\([^\)]*\)/g);
     if (matches !== null) {
       for (var i = 0; i < matches.length; ++i) {
-        var url = /url\(([^\)]*)\)/g.exec(matches[i])[1];
+        var url;
+        if (/url\(\"([^\)]*)\"\)/g.test(matches[i]))
+          url = /url\(\"([^\)]*)\"\)/g.exec(matches[i])[1];
+        else
+          url = /url\(([^\)]*)\)/g.exec(matches[i])[1];
         anchor.href = url;
         anchor.pathname = '...' + anchor.pathname.substring(anchor.pathname.lastIndexOf('/'));
         value = value.replace(matches[i], 'url(' + anchor.href + ')');
       }
     }
     return value;
   }
 
   function normalizeValue(value) {
     return roundNumbers(sanitizeUrls(value)).
@@ skipping 183 matching lines @@
   loadScript('../../resources/testharness.js').then(function() {
     return loadScript('../../resources/testharnessreport.js');
   }).then(function() {
     var asyncHandle = async_test('This test uses interpolation-test.js.')
     requestAnimationFrame(function() {
       runTests();
       asyncHandle.done()
     });
   });
 })();