[PageLoadMetrics] Record bytes usage per page

chrome/browser/page_load_metrics/metrics_web_contents_observer.cc

 // 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.
 
 #include "chrome/browser/page_load_metrics/metrics_web_contents_observer.h"
 
 #include <algorithm>
 #include <ostream>
 #include <string>
 #include <utility>
@@ skipping 160 matching lines @@
       navigation_handle,
       base::MakeUnique<PageLoadTracker>(
           in_foreground_, embedder_interface_.get(), currently_committed_url,
           navigation_handle, user_initiated_info, chain_size,
           chain_size_same_url)));
 }
 
 void MetricsWebContentsObserver::OnRequestComplete(
     content::ResourceType resource_type,
     bool was_cached,
-    int net_error) {
-  // For simplicity, only count subresources. Navigations are hard to attribute
-  // here because we won't have a committed load by the time data streams in
-  // from the IO thread.
-  if (resource_type == content::RESOURCE_TYPE_MAIN_FRAME &&
-      net_error != net::OK) {
+    int64_t raw_body_bytes,
+    base::TimeTicks creation_time) {
+  // If the navigation hasn't committed yet then we'll miss the resource (this
+  // happens on the new tab page). Also, if the resource request was started
+  // before this navigation then it should be ignored.
+  // TODO(jkarlin): There is a race here. If a renderer starts URLRequests for
+  // page A after navigating (but before comitting) to page B, then page A's
+  // requests might wind up counting toward page B's size. This should be
+  // relatively rare but we may want to fix this at some point.
+  if (!committed_load_ || creation_time < committed_load_->navigation_start()) {
     return;
   }
-  if (!committed_load_)
-    return;
-  committed_load_->OnLoadedSubresource(was_cached);
+
+  committed_load_->OnLoadedResource(was_cached, raw_body_bytes);
 }
 
 const PageLoadExtraInfo
 MetricsWebContentsObserver::GetPageLoadExtraInfoForCommittedLoad() {
   DCHECK(committed_load_);
   return committed_load_->ComputePageLoadExtraInfo();
 }
 
 void MetricsWebContentsObserver::DidFinishNavigation(
     content::NavigationHandle* navigation_handle) {
@@ skipping 272 matching lines @@
     content::NavigationHandle* navigation_handle) const {
   DCHECK(navigation_handle->IsInMainFrame());
   DCHECK(!navigation_handle->HasCommitted() ||
          !navigation_handle->IsSamePage());
 
   return BrowserPageTrackDecider(embedder_interface_.get(), web_contents(),
                                  navigation_handle).ShouldTrack();
 }
 
 }  // namespace page_load_metrics