Change NavigationController::LoadURL to take a Referrer class instead of a GURL as referrer

chrome/browser/ui/views/constrained_html_delegate_gtk.cc

Index: chrome/browser/ui/views/constrained_html_delegate_gtk.cc
diff --git a/chrome/browser/ui/views/constrained_html_delegate_gtk.cc b/chrome/browser/ui/views/constrained_html_delegate_gtk.cc
index bbb7548d240ed26f2499916f4347920808496ce1..3638b8cf9926e5a7d68a9dca0706e826ed9c6577 100644
--- a/chrome/browser/ui/views/constrained_html_delegate_gtk.cc
+++ b/chrome/browser/ui/views/constrained_html_delegate_gtk.cc
@@ -103,7 +103,8 @@ ConstrainedHtmlDelegateGtk::ConstrainedHtmlDelegateGtk(
   // Set |this| as a property so the ConstrainedHtmlUI can retrieve it.
   ConstrainedHtmlUI::GetPropertyAccessor().SetProperty(
       tab_contents->property_bag(), this);
-  tab_contents->controller().LoadURL(delegate->GetDialogContentURL(), GURL(),
+  tab_contents->controller().LoadURL(delegate->GetDialogContentURL(),
+                                     content::Referrer(),
                                      content::PAGE_TRANSITION_START_PAGE,
                                      std::string());