Add test data for spaceport benchmark.

chrome/test/data/third_party/spaceport/js/util/bench.js

+define([ ], function () {
+    // Benchmarks fn until maxTime ms has passed.  Returns approximate number
+    // of operations performed in that time ('score').
+    function bench(maxTime, fn) {
+        if (typeof fn !== 'function') {
+            throw new TypeError('Argument must be a function');
+        }
+
+        var operationCount = 0;
+        var startTime = Date.now();
+        var endTime;
+        while (true) {
+            fn(operationCount);
+            ++operationCount;
+
+            endTime = Date.now();
+            if (endTime - startTime >= maxTime) {
+                break;
+            }
+        }
+
+        return operationCount / (endTime - startTime) * maxTime;
+    }
+
+    return bench;
+});