[Prerender] first contentful paint histograms.

chrome/browser/prerender/prerender_test_utils.h

 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_PRERENDER_PRERENDER_TEST_UTILS_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_TEST_UTILS_H_
 
 #include <deque>
 #include <functional>
 #include <memory>
 #include <set>
 #include <string>
 #include <unordered_map>
 #include <vector>
 
 #include "base/memory/weak_ptr.h"
 #include "base/run_loop.h"
 #include "base/test/histogram_tester.h"
 #include "chrome/browser/external_protocol/external_protocol_handler.h"
+#include "chrome/browser/page_load_metrics/observers/prerender_page_load_metrics_observer.h"
 #include "chrome/browser/prerender/prerender_contents.h"
 #include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/browser/safe_browsing/test_safe_browsing_service.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "components/safe_browsing_db/test_database_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/test/url_request/url_request_mock_http_job.h"
 #include "net/url_request/url_request_interceptor.h"
 #include "url/gurl.h"
 
@@ skipping 205 matching lines @@
   void MarkDestruction(FinalStatus reason);
 
   base::RunLoop wait_loop_;
   FinalStatus expected_final_status_;
   bool saw_correct_status_;
   std::unique_ptr<DestructionMarker> marker_;
 
   DISALLOW_COPY_AND_ASSIGN(DestructionWaiter);
 };
 
+// Wait until a PrerenderManager has seen a first contentful paint.
+class FirstContentfulPaintManagerWaiter : public PrerenderManagerObserver {
+ public:
+  // Create and return a pointer to a |FirstContentfulPaintManagerWaiter|. The
+  // instance is owned by the |PrerenderManager|.
+  static FirstContentfulPaintManagerWaiter* Create(PrerenderManager* manager);
+  ~FirstContentfulPaintManagerWaiter();
+
+  void OnFirstContentfulPaint() override;
+
+  // Wait for a first contentful paint to be seen by our PrerenderManager.
+  void Wait();
+
+ private:
+  FirstContentfulPaintManagerWaiter();
+
+  std::unique_ptr<base::RunLoop> waiter_;
+  bool saw_fcp_;
+};
+
 // PrerenderContentsFactory that uses TestPrerenderContents.
 class TestPrerenderContentsFactory : public PrerenderContents::Factory {
  public:
   TestPrerenderContentsFactory();
 
   ~TestPrerenderContentsFactory() override;
 
   std::unique_ptr<TestPrerender> ExpectPrerenderContents(
       FinalStatus final_status);
 
@@ skipping 106 matching lines @@
       safe_browsing_factory_;
   TestPrerenderContentsFactory* prerender_contents_factory_;
   Browser* explicitly_set_browser_;
   bool autostart_test_server_;
   base::HistogramTester histogram_tester_;
   std::unique_ptr<net::EmbeddedTestServer> https_src_server_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderInProcessBrowserTest);
 };
 
+// A test observer that allows the observed navigation start time to be set.
+class TestPrerenderPageLoadMetricsObserver
+    : public PrerenderPageLoadMetricsObserver {
+ public:
+  using PrerenderPageLoadMetricsObserver::PrerenderPageLoadMetricsObserver;
+
+  void SetNavigationStartMilliseconds(int ms) {
+    SetNavigationStartTicksForTesting(base::TimeTicks() +
+                                      base::TimeDelta::FromMilliseconds(ms));
+  }
+
+  void SetNavigationStartFromZero(base::TimeDelta delta) {
+    SetNavigationStartTicksForTesting(base::TimeTicks() + delta);
+  }
+};
+
 // Makes |url| respond to requests with the contents of |file|, counting the
 // number that start in |counter|.
 void CreateCountingInterceptorOnIO(
     const GURL& url,
     const base::FilePath& file,
     const base::WeakPtr<RequestCounter>& counter);
 
 // Makes |url| respond to requests with the contents of |file|.
 void CreateMockInterceptorOnIO(const GURL& url, const base::FilePath& file);
 
 }  // namespace test_utils
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_TEST_UTILS_H_