This patch uses the WebContents' opener to extract the previous committed url for the very first na…

components/page_load_metrics/browser/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 COMPONENTS_PAGE_LOAD_METRICS_BROWSER_METRICS_WEB_CONTENTS_OBSERVER_H_
 #define COMPONENTS_PAGE_LOAD_METRICS_BROWSER_METRICS_WEB_CONTENTS_OBSERVER_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 93 matching lines @@
 // MetricsWebContentsObserver manages a set of provisional PageLoadTrackers, as
 // well as a committed PageLoadTracker.
 class PageLoadTracker {
  public:
   // Caller must guarantee that the embedder_interface pointer outlives this
   // class. The PageLoadTracker must not hold on to
   // currently_committed_load_or_null or navigation_handle beyond the scope of
   // the constructor.
   PageLoadTracker(bool in_foreground,
                   PageLoadMetricsEmbedderInterface* embedder_interface,
-                  PageLoadTracker* const currently_committed_load_or_null,
+                  const GURL& currently_committed_url,
                   content::NavigationHandle* navigation_handle,
                   int aborted_chain_size,
                   int aborted_chain_size_same_url);
   ~PageLoadTracker();
   void Redirect(content::NavigationHandle* navigation_handle);
   void Commit(content::NavigationHandle* navigation_handle);
   void FailedProvisionalLoad(content::NavigationHandle* navigation_handle);
   void WebContentsHidden();
   void WebContentsShown();
 
@@ skipping 160 matching lines @@
 
   // Tracks aborted provisional loads for a little bit longer than usual (one
   // more navigation commit at the max), in order to better understand how the
   // navigation failed. This is because most provisional loads are destroyed and
   // vanish before we get signal about what caused the abort (new navigation,
   // stop button, etc.).
   std::vector<scoped_ptr<PageLoadTracker>> aborted_provisional_loads_;
 
   scoped_ptr<PageLoadTracker> committed_load_;
 
+  // Has the MWCO observed at least one navigation?
+  bool has_navigated_;
+
   DISALLOW_COPY_AND_ASSIGN(MetricsWebContentsObserver);
 };
 
 }  // namespace page_load_metrics
 
 #endif  // COMPONENTS_PAGE_LOAD_METRICS_BROWSER_METRICS_WEB_CONTENTS_OBSERVER_H_