[Not for review] record detailed time breakdown of SW related requests.

content/child/resource_dispatcher.cc

Index: content/child/resource_dispatcher.cc
diff --git a/content/child/resource_dispatcher.cc b/content/child/resource_dispatcher.cc
index 485168c074b536f028835996dcd879dbb6714c90..d74629036880e5c73505dcbe0c2de4e447d4a54b 100644
--- a/content/child/resource_dispatcher.cc
+++ b/content/child/resource_dispatcher.cc
@@ -180,7 +180,6 @@ void ResourceDispatcher::OnReceivedResponse(
     DCHECK(new_peer);
     request_info->peer = std::move(new_peer);
   }
-
   ResourceResponseInfo renderer_response_info;
   ToResourceResponseInfo(*request_info, response_head, &renderer_response_info);
   request_info->site_isolation_metadata =
@@ -188,6 +187,7 @@ void ResourceDispatcher::OnReceivedResponse(
           request_info->frame_origin, request_info->response_url,
           request_info->resource_type, request_info->origin_pid,
           renderer_response_info);
+  renderer_response_info.response_start = response_head.response_start;
   request_info->peer->OnReceivedResponse(renderer_response_info);
 }
 
@@ -668,6 +668,7 @@ int ResourceDispatcher::StartAsync(
     resource_scheduling_filter_->SetRequestIdTaskRunner(request_id,
                                                         loading_task_runner);
   }
+  request->request_start = pending_requests_[request_id]->request_start;
 
   if (ipc_type == blink::WebURLRequest::LoadingIPCType::Mojo) {
     std::unique_ptr<URLLoaderClientImpl> client(