Refactor of various layout tests to use RAF

LayoutTests/svg/custom/js-late-pattern-and-object-creation.svg

 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1 Basic//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-basic.dtd">  
 <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"  id="svg-root" width="100%" height="100%" viewBox="0 0 480 360" onload="runRepaintAndPixelTest()">
 <script xlink:href="../../fast/repaint/resources/text-based-repaint.js"/>
 <g id="content"/>
 
 <script>
     window.testIsAsync = true;
     var content = document.getElementById("content");
 
     function repaintTest() {
-        setTimeout(createPatterns, 0);
+        requestAnimationFrame(createPatterns);
     }
 
     function createPatterns()
     {
         // Setup "fillPattern"    
         var pattern1 = document.createElementNS("http://www.w3.org/2000/svg", "pattern");
         pattern1.setAttribute("id", "fillPattern");
         pattern1.setAttribute("patternUnits", "userSpaceOnUse");
         pattern1.setAttribute("x", "0");
         pattern1.setAttribute("y", "0");
@@ skipping 40 matching lines @@
         rect22.setAttribute("y", "10");
         rect22.setAttribute("width", "10");
         rect22.setAttribute("height", "10");
         rect22.setAttribute("fill", "blue");
 
         pattern2.appendChild(rect12);
         pattern2.appendChild(rect22);
 
         content.appendChild(pattern2);
 
-        setTimeout(setupPatternUsers, 0);
+        requestAnimationFrame(setupPatternUsers);
     }
 
     function setupPatternUsers()
     {
         var text1 = document.createElementNS("http://www.w3.org/2000/svg", "text");
         text1.setAttribute("font-size", "68");
         text1.setAttribute("x", "-150");
         text1.setAttribute("y", "70")
         text1.setAttribute("fill", "url(#fillPattern)");
         text1.setAttribute("stroke", "none");
@@ skipping 19 matching lines @@
         text3.setAttribute("stroke", "url(#strokePattern)");
         text3.appendChild(document.createTextNode("Pattern on fill/stroke"));
 
         content.appendChild(text3);
 
         finishRepaintTest();
     }
 </script>
 
 </svg>