Add support for tracking loading behavior of child frames.

chrome/renderer/chrome_content_renderer_client.cc

 // Copyright (c) 2012 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/chrome_content_renderer_client.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 501 matching lines @@
   safe_browsing::ThreatDOMDetails::Create(render_frame);
 #endif
 
 #if BUILDFLAG(ENABLE_PRINTING)
   new printing::PrintWebViewHelper(
       render_frame, base::MakeUnique<ChromePrintWebViewHelperDelegate>());
 #endif
 
   new NetErrorHelper(render_frame);
 
-  if (render_frame->IsMainFrame()) {
-    // Only attach MetricsRenderFrameObserver to the main frame, since
-    // we only want to log page load metrics for the main frame.
-    new page_load_metrics::MetricsRenderFrameObserver(render_frame);
-  } else {
+  new page_load_metrics::MetricsRenderFrameObserver(render_frame);
+
+  if (!render_frame->IsMainFrame() &&
+      prerender::PrerenderHelper::IsPrerendering(
+          render_frame->GetRenderView()->GetMainRenderFrame())) {
     // Avoid any race conditions from having the browser tell subframes that
     // they're prerendering.
-    if (prerender::PrerenderHelper::IsPrerendering(
-            render_frame->GetRenderView()->GetMainRenderFrame())) {
-      new prerender::PrerenderHelper(render_frame);
-    }
+    new prerender::PrerenderHelper(render_frame);
   }
 
   // Set up a mojo service to test if this page is a distiller page.
   new dom_distiller::DistillerJsRenderFrameObserver(
       render_frame, chrome::ISOLATED_WORLD_ID_CHROME_INTERNAL);
 
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(switches::kEnableDistillabilityService)) {
     // Create DistillabilityAgent to send distillability updates to
     // DistillabilityDriver in the browser process.
@@ skipping 971 matching lines @@
     std::vector<base::SchedulerWorkerPoolParams>* params_vector,
     base::TaskScheduler::WorkerPoolIndexForTraitsCallback*
         index_to_traits_callback) {
   DCHECK(params_vector);
   DCHECK(index_to_traits_callback);
   // If this call fails, content will fall back to the default params.
   *params_vector = task_scheduler_util::GetRendererWorkerPoolParams();
   *index_to_traits_callback =
       base::Bind(&task_scheduler_util::RendererWorkerPoolIndexForTraits);
 }