feat(benchpress): add custom user metric to benchpress

This is a continuation of #7440 (@jeffbcross).

Closes #9229

modules/benchpress/test/metric/user_metric_spec.ts

@@ -0,0 +1,101 @@
+import {ReflectiveInjector} from "angular2/core";
+import {
+  afterEach,
+  AsyncTestCompleter,
+  beforeEach,
+  ddescribe,
+  describe,
+  expect,
+  iit,
+  inject,
+  it,
+  xit
+} from 'angular2/testing_internal';
+
+import {TimerWrapper} from 'angular2/src/facade/async';
+import {StringMapWrapper} from 'angular2/src/facade/collection';
+import {PromiseWrapper} from 'angular2/src/facade/async';
+import {isPresent, isBlank, Json} from 'angular2/src/facade/lang';
+
+import {
+  Metric,
+  MultiMetric,
+  PerflogMetric,
+  UserMetric,
+  WebDriverAdapter,
+  WebDriverExtension,
+  PerfLogFeatures,
+  bind,
+  provide,
+  Injector,
+  Options
+} from 'benchpress/common';
+
+export function main() {
+  var wdAdapter: MockDriverAdapter;
+
+  function createMetric(perfLogs, perfLogFeatures,
+                        {userMetrics}: {userMetrics?: {[key: string]: string}} = {}): UserMetric {
+    if (isBlank(perfLogFeatures)) {
+      perfLogFeatures =
+          new PerfLogFeatures({render: true, gc: true, frameCapture: true, userTiming: true});
+    }
+    if (isBlank(userMetrics)) {
+      userMetrics = StringMapWrapper.create();
+    }
+    wdAdapter = new MockDriverAdapter();
+    var bindings = [
+      Options.DEFAULT_PROVIDERS,
+      UserMetric.BINDINGS,
+      bind(Options.USER_METRICS).toValue(userMetrics),
+      provide(WebDriverAdapter, {useValue: wdAdapter})
+    ];
+    return ReflectiveInjector.resolveAndCreate(bindings).get(UserMetric);
+  }
+
+  describe('user metric', () => {
+
+    it('should describe itself based on userMetrics', () => {
+      expect(createMetric([[]], new PerfLogFeatures(), {userMetrics: {'loadTime': 'time to load'}})
+                 .describe())
+          .toEqual({'loadTime': 'time to load'});
+    });
+
+    describe('endMeasure', () => {
+      it('should stop measuring when all properties have numeric values',
+         inject([AsyncTestCompleter], (async) => {
+           let metric = createMetric(
+               [[]], new PerfLogFeatures(),
+               {userMetrics: {'loadTime': 'time to load', 'content': 'time to see content'}});
+           metric.beginMeasure()
+               .then((_) => metric.endMeasure(true))
+               .then((values: {[key: string]: string}) => {
+                 expect(values['loadTime']).toBe(25);
+                 expect(values['content']).toBe(250);
+                 async.done();
+               });
+
+           wdAdapter.data['loadTime'] = 25;
+           // Wait before setting 2nd property.
+           TimerWrapper.setTimeout(() => { wdAdapter.data['content'] = 250; }, 50);
+
+         }), 600);
+    });
+  });
+}
+
+class MockDriverAdapter extends WebDriverAdapter {
+  data: any = {};
+
+  executeScript(script: string): any {
+    // Just handles `return window.propName` ignores `delete window.propName`.
+    if (script.indexOf('return window.') == 0) {
+      let metricName = script.substring('return window.'.length);
+      return PromiseWrapper.resolve(this.data[metricName]);
+    } else if (script.indexOf('delete window.') == 0) {
+      return PromiseWrapper.resolve(null);
+    } else {
+      return PromiseWrapper.reject(`Unexpected syntax: ${script}`, null);
+    }
+  }
+}