Adding DRP specfic UMA for FirstContentfulPaint

content/browser/loader/resource_dispatcher_host_impl.cc

Index: content/browser/loader/resource_dispatcher_host_impl.cc
diff --git a/content/browser/loader/resource_dispatcher_host_impl.cc b/content/browser/loader/resource_dispatcher_host_impl.cc
index e594cb76d5aef0b6545234d41d7bfa1bb0eee8c1..309a639c1ff228d283837d0d4e3bed7fd6c63d30 100644
--- a/content/browser/loader/resource_dispatcher_host_impl.cc
+++ b/content/browser/loader/resource_dispatcher_host_impl.cc
@@ -1725,21 +1725,21 @@ ResourceDispatcherHostImpl::AddStandardHandlers(
   // Insert a buffered event handler before the actual one.
   handler.reset(new MimeTypeResourceHandler(std::move(handler), this,
                                             plugin_service, request));
 
   ScopedVector<ResourceThrottle> throttles;
 
   // Add a NavigationResourceThrottle for navigations.
   // PlzNavigate: the throttle is unnecessary as communication with the UI
   // thread is handled by the NavigationURLloader.
   if (!IsBrowserSideNavigationEnabled() && IsResourceTypeFrame(resource_type))
-    throttles.push_back(new NavigationResourceThrottle(request));
+    throttles.push_back(new NavigationResourceThrottle(request, this));
 
   if (delegate_) {
     delegate_->RequestBeginning(request,
                                 resource_context,
                                 appcache_service,
                                 resource_type,
                                 &throttles);
   }
 
   if (request->has_upload()) {
@@ -2322,21 +2322,21 @@ void ResourceDispatcherHostImpl::BeginNavigationRequest(
       info.is_main_frame ? REQUEST_CONTEXT_FRAME_TYPE_TOP_LEVEL
                          : REQUEST_CONTEXT_FRAME_TYPE_NESTED;
   ServiceWorkerRequestHandler::InitializeForNavigation(
       new_request.get(), service_worker_handle_core, blob_context,
       info.begin_params.skip_service_worker, resource_type,
       info.begin_params.request_context_type, frame_type, info.request_body);
 
   // TODO(davidben): Attach AppCacheInterceptor.
 
   std::unique_ptr<ResourceHandler> handler(
-      new NavigationResourceHandler(new_request.get(), loader));
+      new NavigationResourceHandler(new_request.get(), loader, this));

[bengr, 2016/04/29 21:14:23]

I find it a little weird that NRH takes an Impl object, but they are in the same
directory, so I suppose it's ok. 

[RyanSturm, 2016/05/02 19:52:22]

I suppose this could take an rdhd instead, but I prefer rdh.

 
   // TODO(davidben): Pass in the appropriate appcache_service. Also fix the
   // dependency on child_id/route_id. Those are used by the ResourceScheduler;
   // currently it's a no-op.
   handler =
       AddStandardHandlers(new_request.get(), resource_type, resource_context,
                           nullptr,  // appcache_service
                           -1,       // child_id
                           -1,       // route_id
                           std::move(handler));