Constify the rendering/ selection code

Source/core/rendering/RootInlineBox.h

 /*
  * Copyright (C) 2003, 2006, 2007, 2008 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 100 matching lines @@
 
     virtual int baselinePosition(FontBaseline baselineType) const OVERRIDE FINAL;
     virtual LayoutUnit lineHeight() const OVERRIDE FINAL;
 
     virtual void paint(PaintInfo&, const LayoutPoint&, LayoutUnit lineTop, LayoutUnit lineBottom) OVERRIDE;
     virtual bool nodeAtPoint(const HitTestRequest&, HitTestResult&, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, LayoutUnit lineTop, LayoutUnit lineBottom) OVERRIDE FINAL;
 
     using InlineBox::hasSelectedChildren;
     using InlineBox::setHasSelectedChildren;
 
-    virtual RenderObject::SelectionState selectionState() OVERRIDE FINAL;
-    InlineBox* firstSelectedBox();
-    InlineBox* lastSelectedBox();
+    virtual RenderObject::SelectionState selectionState() const OVERRIDE FINAL;
+    InlineBox* firstSelectedBox() const;
+    InlineBox* lastSelectedBox() const;
 
-    GapRects lineSelectionGap(RenderBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock, LayoutUnit selTop, LayoutUnit selHeight, const PaintInfo*);
+    GapRects lineSelectionGap(const RenderBlock* rootBlock, const LayoutPoint& rootBlockPhysicalPosition, const LayoutSize& offsetFromRootBlock, LayoutUnit selTop, LayoutUnit selHeight, const PaintInfo*) const;
 
     RenderBlockFlow& block() const;
 
     InlineBox* closestLeafChildForPoint(const IntPoint&, bool onlyEditableLeaves);
     InlineBox* closestLeafChildForLogicalLeftPosition(int, bool onlyEditableLeaves = false);
 
     void appendFloat(RenderBox* floatingBox)
     {
         ASSERT(!isDirty());
         if (m_floats)
@@ skipping 95 matching lines @@
     LayoutUnit m_lineTop;
     LayoutUnit m_lineBottom;
     LayoutUnit m_lineTopWithLeading;
     LayoutUnit m_lineBottomWithLeading;
     LayoutUnit m_selectionBottom;
 };
 
 } // namespace blink
 
 #endif // RootInlineBox_h