Add support for tracking loading behavior of child frames.

chrome/renderer/page_load_metrics/metrics_render_frame_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/renderer/page_load_metrics/metrics_render_frame_observer.h"
 
 #include <string>
 
 #include "base/memory/ptr_util.h"
 #include "base/time/time.h"
@@ skipping 20 matching lines @@
 
 }  //  namespace
 
 MetricsRenderFrameObserver::MetricsRenderFrameObserver(
     content::RenderFrame* render_frame)
     : content::RenderFrameObserver(render_frame) {}
 
 MetricsRenderFrameObserver::~MetricsRenderFrameObserver() {}
 
 void MetricsRenderFrameObserver::DidChangePerformanceTiming() {
-  SendMetrics();
+  // Only track timing metrics for main frames.
+  if (IsMainFrame())
+    SendMetrics();
 }
 
 void MetricsRenderFrameObserver::DidObserveLoadingBehavior(
     blink::WebLoadingBehaviorFlag behavior) {
   if (page_timing_metrics_sender_)
     page_timing_metrics_sender_->DidObserveLoadingBehavior(behavior);
 }
 
+void MetricsRenderFrameObserver::FrameDetached() {
+  page_timing_metrics_sender_.reset();
+}
+
 void MetricsRenderFrameObserver::DidCommitProvisionalLoad(
     bool is_new_navigation,
     bool is_same_page_navigation) {
   // Same-page navigations (e.g. an in-document navigation from a fragment
   // link) aren't full page loads, since they don't go to network to load the
   // main HTML resource. DidStartProvisionalLoad doesn't get invoked for same
   // page navigations, so we may still have an active
   // page_timing_metrics_sender_ at this point.
   if (is_same_page_navigation)
     return;
 
   // Make sure to release the sender for a previous navigation, if we have one.
   page_timing_metrics_sender_.reset();
 
   // We only create a PageTimingMetricsSender if the page meets the criteria for
   // sending and recording metrics. Once page_timing_metrics_sender_ is
   // non-null, we will send metrics for the current page at some later time, as
   // those metrics become available.
   if (ShouldSendMetrics()) {
-    PageLoadTiming timing(GetTiming());
-    DCHECK(!timing.navigation_start.is_null());
+    PageLoadTiming timing;
+    if (IsMainFrame()) {
+      // Only populate PageLoadTiming for the main frame.
+      timing = GetTiming();
+      DCHECK(!timing.navigation_start.is_null());
+    }
     page_timing_metrics_sender_.reset(
         new PageTimingMetricsSender(this, routing_id(), CreateTimer(), timing));
   }
 }
 
 void MetricsRenderFrameObserver::SendMetrics() {
   if (!page_timing_metrics_sender_)
     return;
   if (HasNoRenderFrame())
     return;
   PageLoadTiming timing(GetTiming());
   page_timing_metrics_sender_->Send(timing);
 }
 
 bool MetricsRenderFrameObserver::ShouldSendMetrics() const {
   if (HasNoRenderFrame())
     return false;
   const blink::WebLocalFrame* frame = render_frame()->GetWebFrame();
-  // We only track metrics for main frames.
-  if (frame->parent())
-    return false;
-
   const blink::WebDocument& document = frame->document();
   return RendererPageTrackDecider(&document, frame->dataSource()).ShouldTrack();
 }
 
 PageLoadTiming MetricsRenderFrameObserver::GetTiming() const {
   const blink::WebPerformance& perf =
       render_frame()->GetWebFrame()->performance();
 
   PageLoadTiming timing;
   double start = perf.navigationStart();
@@ skipping 61 matching lines @@
 bool MetricsRenderFrameObserver::HasNoRenderFrame() const {
   bool no_frame = !render_frame() || !render_frame()->GetWebFrame();
   DCHECK(!no_frame);
   return no_frame;
 }
 
 void MetricsRenderFrameObserver::OnDestruct() {
   delete this;
 }
 
+bool MetricsRenderFrameObserver::IsMainFrame() const {
+  return render_frame()->IsMainFrame();
+}
+
 }  // namespace page_load_metrics