Make PageLoadMetricsWaiter more resilient

chrome/browser/page_load_metrics/metrics_web_contents_observer.h

 // Copyright 2015 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_PAGE_LOAD_METRICS_METRICS_WEB_CONTENTS_OBSERVER_H_
 #define CHROME_BROWSER_PAGE_LOAD_METRICS_METRICS_WEB_CONTENTS_OBSERVER_H_
 
 #include <map>
 #include <memory>
 #include <vector>
@@ skipping 42 matching lines @@
   // have been observed.
   class TestingObserver {
    public:
     enum class IPCType { LEGACY, MOJO };
 
     explicit TestingObserver(content::WebContents* web_contents);
     virtual ~TestingObserver();
 
     void OnGoingAway();
 
-    // Invoked when a new PageLoadTiming update has been received and processed.
-    virtual void OnTimingUpdated(bool is_main_frame,
-                                 const mojom::PageLoadTiming& timing,
-                                 const mojom::PageLoadMetadata& metadata) {}
-
+    virtual void OnCommit(PageLoadTracker* tracker) {}
     virtual void DidReceiveTimingUpdate(IPCType type) {}
 
    private:
     page_load_metrics::MetricsWebContentsObserver* observer_;
 
     DISALLOW_COPY_AND_ASSIGN(TestingObserver);
   };
 
   // Note that the returned metrics is owned by the web contents.
   static MetricsWebContentsObserver* CreateForWebContents(
@@ skipping 155 matching lines @@
   base::ObserverList<TestingObserver> testing_observers_;
   content::WebContentsFrameBindingSet<mojom::PageLoadMetrics>
       page_load_metrics_binding_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsWebContentsObserver);
 };
 
 }  // namespace page_load_metrics
 
 #endif  // CHROME_BROWSER_PAGE_LOAD_METRICS_METRICS_WEB_CONTENTS_OBSERVER_H_