Adding DRP specfic UMA for FirstContentfulPaint

content/browser/loader/navigation_resource_handler.cc

 // Copyright 2014 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 "content/browser/loader/navigation_resource_handler.h"
 
+#include <memory>
+
 #include "base/logging.h"
 #include "content/browser/devtools/devtools_netlog_observer.h"
 #include "content/browser/loader/navigation_url_loader_impl_core.h"
+#include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/browser/loader/resource_request_info_impl.h"
 #include "content/browser/resource_context_impl.h"
 #include "content/browser/streams/stream.h"
 #include "content/browser/streams/stream_context.h"
+#include "content/public/browser/navigation_data.h"
 #include "content/public/browser/resource_controller.h"
+#include "content/public/browser/resource_dispatcher_host_delegate.h"
 #include "content/public/browser/stream_handle.h"
 #include "content/public/common/resource_response.h"
 #include "net/base/net_errors.h"
 #include "net/url_request/url_request.h"
 
 namespace content {
 
 NavigationResourceHandler::NavigationResourceHandler(
     net::URLRequest* request,
-    NavigationURLLoaderImplCore* core)
-    : ResourceHandler(request),
-      core_(core) {
+    NavigationURLLoaderImplCore* core,
+    ResourceDispatcherHostImpl* rdh)
+    : ResourceHandler(request), core_(core), rdh_(rdh) {
   core_->set_resource_handler(this);
   writer_.set_immediate_mode(true);
 }
 
 NavigationResourceHandler::~NavigationResourceHandler() {
   if (core_) {
     core_->NotifyRequestFailed(false, net::ERR_ABORTED);
     DetachFromCore();
   }
 }
@@ skipping 48 matching lines @@
   // dispatched at the navigation layer.
   if (info->IsDownload() || info->is_stream())
     return true;
 
   StreamContext* stream_context =
       GetStreamContextForResourceContext(info->GetContext());
   writer_.InitializeStream(stream_context->registry(),
                            request()->url().GetOrigin());
 
   DevToolsNetLogObserver::PopulateResponseInfo(request(), response);
-  core_->NotifyResponseStarted(response, writer_.stream()->CreateHandle());
+
+  // Ask the embedder for a NavigationData instance.
+  std::unique_ptr<NavigationData> navigation_data(nullptr);

[bengr, 2016/04/29 21:14:22]

I'm not sure about Chromium style, but you can do:
std::unique_ptr<NavigationData> navigation_data;

[RyanSturm, 2016/05/02 19:52:21]

Done.

+  if (rdh_ && rdh_->delegate())
+    navigation_data = rdh_->delegate()->GetNavigationData(request());
+  // Clone the embedder NavigationData before moving it to the UI thread.

[bengr, 2016/04/29 21:14:22]

embedder -> embedder's

[RyanSturm, 2016/05/02 19:52:21]

Done.

+  std::unique_ptr<NavigationData> clone_data(
+      navigation_data.get() ? navigation_data->Clone() : nullptr);
+  core_->NotifyResponseStarted(response, writer_.stream()->CreateHandle(),
+                               std::move(clone_data));
   *defer = true;
+
   return true;
 }
 
 bool NavigationResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return true;
 }
 
 bool NavigationResourceHandler::OnBeforeNetworkStart(const GURL& url,
                                                      bool* defer) {
   return true;
@@ skipping 36 matching lines @@
   NOTREACHED();
 }
 
 void NavigationResourceHandler::DetachFromCore() {
   DCHECK(core_);
   core_->set_resource_handler(nullptr);
   core_ = nullptr;
 }
 
 }  // namespace content