Constify the rendering/ selection code

Source/core/rendering/RenderListMarker.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009 Apple 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 52 matching lines @@
 
     virtual InlineBox* createInlineBox() OVERRIDE;
 
     virtual LayoutUnit lineHeight(bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const OVERRIDE;
     virtual int baselinePosition(FontBaseline, bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const OVERRIDE;
 
     virtual bool isImage() const OVERRIDE;
     bool isText() const { return !isImage(); }
 
     virtual void setSelectionState(SelectionState) OVERRIDE;
-    virtual LayoutRect selectionRectForPaintInvalidation(const RenderLayerModelObject* paintInvalidationContainer, bool clipToVisibleContent = true) OVERRIDE;
+    virtual LayoutRect selectionRectForPaintInvalidation(const RenderLayerModelObject* paintInvalidationContainer, bool clipToVisibleContent = true) const OVERRIDE;
     virtual bool canBeSelectionLeaf() const OVERRIDE { return true; }
 
     void updateMargins();
     void updateContent();
 
     virtual void styleWillChange(StyleDifference, const RenderStyle& newStyle) OVERRIDE;
     virtual void styleDidChange(StyleDifference, const RenderStyle* oldStyle) OVERRIDE;
 
     IntRect getRelativeMarkerRect();
     LayoutRect localSelectionRect();
 
     String m_text;
     RefPtr<StyleImage> m_image;
     RawPtrWillBeMember<RenderListItem> m_listItem;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderListMarker, isListMarker());
 
 } // namespace blink
 
 #endif // RenderListMarker_h