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 7b09885c9f353f06f9c4158acf0ada39e32c0240..a1c6e0a4dcb11fb83e7e3956f95e5ea8a7c659cd 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 +330,24 @@ 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).

[nasko, 2014/09/24 00:48:07]

nit: Navigator, you don't have any Impls in the code below.

[carlosk, 2014/09/24 18:35:50]

Done.

+void LogResourceRequestTimeOnUI(
+    base::TimeTicks timestamp,
+    int render_process_id,
+    int render_frame_host,

[nasko, 2014/09/24 00:48:07]

nit: render_frame_id

[carlosk, 2014/09/24 18:35:50]

Done.

+    const GURL& url) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  RenderFrameHostImpl* host =
+      RenderFrameHostImpl::FromID(render_process_id, render_frame_host);
+  if (host != NULL) {
+    DCHECK(host->frame_tree_node()->IsMainFrame());
+    Navigator* navigator = host->frame_tree_node()->navigator();

[nasko, 2014/09/24 00:48:07]

nit: no real need for a stack variable here.

[carlosk, 2014/09/24 18:35:50]

Done.

+    navigator->LogResourceRequestTime(timestamp, url);
+  }
+}
+
 }  // namespace
 
 // static
@@ -888,6 +907,16 @@ void ResourceDispatcherHostImpl::OnRequestResource(
     int routing_id,
     int request_id,
     const ResourceHostMsg_Request& request_data) {
+  if (request_data.resource_type == RESOURCE_TYPE_MAIN_FRAME) {
+    BrowserThread::PostTask(
+        BrowserThread::UI,
+        FROM_HERE,
+        base::Bind(&LogResourceRequestTimeOnUI,
+                   TimeTicks::Now(),
+                   filter_->child_id(),
+                   request_data.render_frame_id,
+                   request_data.url));
+  }
   BeginRequest(request_id, request_data, NULL, routing_id);
 }