Add time-to-network histogram considering browser side navigation

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 ebfce6cdca9ef6cb37e6bf14c1dbb9cd11968d4f..029603378014cb4a57fd2551e552cd056483f576 100644
--- a/content/browser/loader/resource_dispatcher_host_impl.cc
+++ b/content/browser/loader/resource_dispatcher_host_impl.cc
@@ -32,6 +32,7 @@
 #include "content/browser/download/save_file_resource_handler.h"
 #include "content/browser/fileapi/chrome_blob_storage_context.h"
 #include "content/browser/frame_host/navigation_request_info.h"
+#include "content/browser/frame_host/navigator.h"
 #include "content/browser/loader/async_resource_handler.h"
 #include "content/browser/loader/buffered_resource_handler.h"
 #include "content/browser/loader/cross_site_resource_handler.h"
@@ -329,6 +330,25 @@ void AttachRequestBodyBlobDataHandles(
   }
 }
 
+// PlzNavigate
+// This method is called in the UI thread to send the timestamp of a resource
+// request to the respective NavigatorImpl (for an UMA histogram).
+void LogResourceRequestTimeOnUI(
+    base::TimeTicks timestamp, int render_process_id, int render_frame_host) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  RenderFrameHostImpl* host =
+      RenderFrameHostImpl::FromID(render_process_id, render_frame_host);
+  if (host != NULL) {
+    DCHECK(host->frame_tree_node()->IsMainFrame());
+    LOG(WARNING) << "$$$$$$$$$$$$$$$";
+    LOG(WARNING) << "Found RenderFrameHostImpl";
+    LOG(WARNING) << "process_id / child_id = " << render_process_id;
+    LOG(WARNING) << "routing_id / render_frame_host = " << render_frame_host;
+    content::Navigator* navigator = host->frame_tree_node()->navigator();
+    navigator->LogResourceRequestTime(timestamp);
+  }
+}
+
 }  // namespace
 
 // static
@@ -888,6 +908,14 @@ void ResourceDispatcherHostImpl::OnRequestResource(
     int routing_id,
     int request_id,
     const ResourceHostMsg_Request& request_data) {
+  if (request_data.resource_type == RESOURCE_TYPE_MAIN_FRAME) {
+    int child_id = filter_->child_id();
+    BrowserThread::PostTask(
+        BrowserThread::UI,
+        FROM_HERE,
+        base::Bind(&LogResourceRequestTimeOnUI,
+                   TimeTicks::Now(), child_id, request_data.render_frame_id));
+  }
   BeginRequest(request_id, request_data, NULL, routing_id);
 }