Let FullscreenElementStack methods take references where possible

Source/core/dom/RenderTreeBuilder.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 114 matching lines @@
     }
 
     // Make sure the RenderObject already knows it is going to be added to a RenderFlowThread before we set the style
     // for the first time. Otherwise code using inRenderFlowThread() in the styleWillChange and styleDidChange will fail.
     newRenderer->setFlowThreadState(parentRenderer->flowThreadState());
 
     RenderObject* nextRenderer = this->nextRenderer();
     element->setRenderer(newRenderer);
     newRenderer->setStyle(&style); // setStyle() can depend on renderer() already being set.
 
-    if (FullscreenElementStack::isActiveFullScreenElement(element)) {
+    if (FullscreenElementStack::isActiveFullScreenElement(*element)) {
         newRenderer = RenderFullScreen::wrapRenderer(newRenderer, parentRenderer, &element->document());
         if (!newRenderer)
             return;
     }
 
     // Note: Adding newRenderer instead of renderer(). renderer() may be a child of newRenderer.
     parentRenderer->addChild(newRenderer, nextRenderer);
 }
 
 void RenderTreeBuilder::createRendererForTextIfNeeded()
@@ skipping 22 matching lines @@
     newRenderer->setFlowThreadState(parentRenderer->flowThreadState());
 
     RenderObject* nextRenderer = this->nextRenderer();
     textNode->setRenderer(newRenderer);
     // Parent takes care of the animations, no need to call setAnimatableStyle.
     newRenderer->setStyle(m_style.release());
     parentRenderer->addChild(newRenderer, nextRenderer);
 }
 
 }