Navigation transitions: Block first response until after transitions have run.

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index bb52683521205948685da4ad3e51949ed4ea9324..398fd66d639e84ba735af8a5e9423ab286a72540 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -846,6 +846,11 @@ void RenderProcessHostImpl::ResumeDeferredNavigation(
   widget_helper_->ResumeDeferredNavigation(request_id);
 }
 
+void RenderProcessHostImpl::ResumeResponseDeferredAtStart(
+    const GlobalRequestID& request_id) {
+  widget_helper_->ResumeResponseDeferredAtStart(request_id);
+}
+
 void RenderProcessHostImpl::NotifyTimezoneChange() {
   Send(new ViewMsg_TimezoneChange());
 }