Add fast path for querySelector(All)

PerformanceTests/Parser/query-selector-all-class-deep.html

Index: PerformanceTests/Parser/query-selector-all-class-deep.html
diff --git a/PerformanceTests/Parser/query-selector-id-deep.html b/PerformanceTests/Parser/query-selector-all-class-deep.html
similarity index 69%
copy from PerformanceTests/Parser/query-selector-id-deep.html
copy to PerformanceTests/Parser/query-selector-all-class-deep.html
index 3b9fc1aa75ab8732f238dac65af46c8e8fdd17d7..763204419d50c479414e2fece295da8cd2284127 100644
--- a/PerformanceTests/Parser/query-selector-id-deep.html
+++ b/PerformanceTests/Parser/query-selector-all-class-deep.html
@@ -18,10 +18,10 @@ h1.className = "class";
 parentDiv.appendChild(h1);
 
 PerfTestRunner.measureRunsPerSecond({
-    description: "This benchmark tests querySelector() for an element that appears in the depths in the document, and is a descendant of an element with a given id",
+    description: "This benchmark tests querySelectorAll() for an element that appears in the depths in the document, and is a descendant of an element with a given class name",
     run: function() {
         for (var i = 0; i < 100; i++) {
-            var res = document.querySelector("#foo998 h1");
+            var res = document.querySelectorAll(".bar998 h1");
         }
     }});
 </script>