[PageLoadMetrics] Record bytes usage per page

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 54 matching lines @@
   void RenderProcessGone(base::TerminationStatus status) override;
   void RenderViewHostChanged(content::RenderViewHost* old_host,
                              content::RenderViewHost* new_host) override;
 
   // This method is forwarded from the MetricsNavigationThrottle.
   void WillStartNavigationRequest(content::NavigationHandle* navigation_handle);
 
   // A resource request completed on the IO thread.
   void OnRequestComplete(content::ResourceType resource_type,
                          bool was_cached,
-                         int net_error);
+                         int64_t raw_body_bytes,
+                         base::TimeTicks creation_time);
 
   // Flush any buffered metrics, as part of the metrics subsystem persisting
   // metrics as the application goes into the background. The application may be
   // killed at any time after this method is invoked without further
   // notification.
   void FlushMetricsOnAppEnterBackground();
 
   // This getter function is required for testing.
   const PageLoadExtraInfo GetPageLoadExtraInfoForCommittedLoad();
 
@@ skipping 61 matching lines @@
 
   // Has the MWCO observed at least one navigation?
   bool has_navigated_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsWebContentsObserver);
 };
 
 }  // namespace page_load_metrics
 
 #endif  // CHROME_BROWSER_PAGE_LOAD_METRICS_METRICS_WEB_CONTENTS_OBSERVER_H_