Have Node::document() return a reference instead of a pointer

Source/core/rendering/RenderWidget.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2006, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 65 matching lines @@
         else
             child->removeFromParent();
         return;
     }
     WidgetHierarchyUpdatesSuspensionScope::scheduleWidgetToMove(child, parent);
 }
 
 RenderWidget::RenderWidget(Element* element)
     : RenderReplaced(element)
     , m_widget(0)
-    , m_frameView(element->document()->view())
+    , m_frameView(element->document().view())
     // Reference counting is used to prevent the widget from being
     // destroyed while inside the Widget code, which might not be
     // able to handle that.
     , m_refCount(1)
 {
     view()->addWidget(this);
 }
 
 void RenderWidget::willBeDestroyed()
 {
     if (RenderView* v = view())
         v->removeWidget(this);
 
-    if (AXObjectCache* cache = document()->existingAXObjectCache()) {
+    if (AXObjectCache* cache = document().existingAXObjectCache()) {
         cache->childrenChanged(this->parent());
         cache->remove(this);
     }
 
     setWidget(0);
 
     RenderReplaced::willBeDestroyed();
 }
 
 void RenderWidget::destroy()
@@ skipping 80 matching lines @@
             if (style()->visibility() != VISIBLE)
                 m_widget->hide();
             else {
                 m_widget->show();
                 repaint();
             }
         }
         moveWidgetToParentSoon(m_widget.get(), m_frameView);
     }
 
-    if (AXObjectCache* cache = document()->existingAXObjectCache())
+    if (AXObjectCache* cache = document().existingAXObjectCache())
         cache->childrenChanged(this);
 }
 
 void RenderWidget::layout()
 {
     ASSERT(needsLayout());
 
     clearNeedsLayout();
 }
 
@@ skipping 77 matching lines @@
         clipRoundedInnerRect(paintInfo.context, borderRect, roundedInnerRect);
     }
 
     if (m_widget)
         paintContents(paintInfo, paintOffset);
 
     if (style()->hasBorderRadius())
         paintInfo.context->restore();
 
     // Paint a partially transparent wash over selected widgets.
-    if (isSelected() && !document()->printing()) {
+    if (isSelected() && !document().printing()) {
         // FIXME: selectionRect() is in absolute, not painting coordinates.
         paintInfo.context->fillRect(pixelSnappedIntRect(selectionRect()), selectionBackgroundColor());
     }
 
     if (hasLayer() && layer()->canResize())
         layer()->paintResizer(paintInfo.context, roundedIntPoint(adjustedPaintOffset), paintInfo.rect);
 }
 
 void RenderWidget::setIsOverlapped(bool isOverlapped)
 {
@@ skipping 64 matching lines @@
 CursorDirective RenderWidget::getCursor(const LayoutPoint& point, Cursor& cursor) const
 {
     if (widget() && widget()->isPluginView()) {
         // A plug-in is responsible for setting the cursor when the pointer is over it.
         return DoNotSetCursor;
     }
     return RenderReplaced::getCursor(point, cursor);
 }
 
 } // namespace WebCore