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

chrome/browser/ui/views/notifications/balloon_view.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/notifications/balloon_view.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 215 matching lines @@
   anim_frame_start_ = frame_container_->GetClientAreaScreenBounds();
   animation_.reset(new ui::SlideAnimation(this));
   animation_->Show();
 }
 
 void BalloonViewImpl::Update() {
   DCHECK(html_contents_.get()) << "BalloonView::Update called before Show";
   if (!html_contents_->tab_contents())
     return;
   html_contents_->tab_contents()->controller().LoadURL(
-      balloon_->notification().content_url(), GURL(),
+      balloon_->notification().content_url(), content::Referrer(),
       content::PAGE_TRANSITION_LINK, std::string());
 }
 
 void BalloonViewImpl::AnimationProgressed(const ui::Animation* animation) {
   DCHECK(animation == animation_.get());
 
   // Linear interpolation from start to end position.
   double e = animation->GetCurrentValue();
   double s = (1.0 - e);
 
@@ skipping 269 matching lines @@
     return;
   }
 
   // If the renderer process attached to this balloon is disconnected
   // (e.g., because of a crash), we want to close the balloon.
   notification_registrar_.Remove(
       this, chrome::NOTIFICATION_NOTIFY_BALLOON_DISCONNECTED,
       content::Source<Balloon>(balloon_));
   Close(false);
 }