Send an event to the page load metrics to track resource starting.

chrome/browser/page_load_metrics/page_load_tracker.cc

 // Copyright 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.
 
 #include "chrome/browser/page_load_metrics/page_load_tracker.h"
 
 #include <algorithm>
 #include <ostream>
 #include <string>
 #include <utility>
@@ skipping 601 matching lines @@
 
   const PageLoadMetadata last_metadata = main_frame_metadata_;
   main_frame_metadata_ = new_metadata;
   const PageLoadExtraInfo info = ComputePageLoadExtraInfo();
   for (const auto& observer : observers_) {
     DispatchObserverTimingCallbacks(observer.get(), last_timing, new_timing,
                                     last_metadata, info);
   }
 }
 
+void PageLoadTracker::OnStartedResource(
+    const ExtraRequestStartInfo& extra_request_start_info) {
+  for (const auto& observer : observers_) {
+    observer->OnStartedResource(extra_request_start_info);
+  }
+}
+
 void PageLoadTracker::OnLoadedResource(
-    const ExtraRequestInfo& extra_request_info) {
+    const ExtraRequestCompleteInfo& extra_request_complete_info) {
   for (const auto& observer : observers_) {
-    observer->OnLoadedResource(extra_request_info);
+    observer->OnLoadedResource(extra_request_complete_info);
   }
 }
 
 void PageLoadTracker::StopTracking() {
   did_stop_tracking_ = true;
   observers_.clear();
 }
 
 void PageLoadTracker::AddObserver(
     std::unique_ptr<PageLoadMetricsObserver> observer) {
@@ skipping 161 matching lines @@
     observer->MediaStartedPlaying(video_type, is_in_main_frame);
 }
 
 void PageLoadTracker::OnNavigationDelayComplete(base::TimeDelta scheduled_delay,
                                                 base::TimeDelta actual_delay) {
   for (const auto& observer : observers_)
     observer->OnNavigationDelayComplete(scheduled_delay, actual_delay);
 }
 
 }  // namespace page_load_metrics