Add attribute selectors to the SelectorCountScaling performance test.

PerformanceTests/CSS/SelectorCountScaling.html

Index: PerformanceTests/CSS/SelectorCountScaling.html
diff --git a/PerformanceTests/CSS/SelectorCountScaling.html b/PerformanceTests/CSS/SelectorCountScaling.html
index 68a67fe827caa9cf3ff1b93f9e17024f7d44a6f2..881b6da5f6cf9eb82b247667ba3e9141dea6ff6f 100644
--- a/PerformanceTests/CSS/SelectorCountScaling.html
+++ b/PerformanceTests/CSS/SelectorCountScaling.html
@@ -17,18 +17,27 @@ function insertStyleSheet(css)
     return styleElement;
 }
 
-function cssStr(count) {
+function cssStrWithClassSelectors(count) {
     var selector = '.a' + count + ' .b' + count + ' { color: red } ';
     // Intentionally repeat the same classes many times, to test duplicate optimizations.
     return selector + selector + selector + selector + selector + selector + selector;
 }
 
+function cssStrWithAttributeSelectors(count) {
+    var selector = '[attrA' + count + '="1"]' + ' [attrB' + count + '="1"]' + ' { color: red } ';
+    // Intentionally repeat the same classes many times, to test duplicate optimizations.
+    return selector + selector + selector + selector + selector + selector + selector;
+}
+
 function runFunction()
 {
     var numRules = 1000;
     var arr = new Array(numRules);
     for (var i = 0 ; i < numRules; i++) {
-        arr[i] = cssStr(i);
+        arr[i] = cssStrWithClassSelectors(i);
+    }
+    for (var i = 0 ; i < numRules; i++) {
+        arr[numRules + i] = cssStrWithAttributeSelectors(i);
     }
     var styleElement = insertStyleSheet(arr.join(' '));