Implement CSS3TextDecorations runtime flag in favor of CSS3_TEXT

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 163 matching lines @@
     }
     LayoutUnit logicalTopLayoutOverflow() const
     {
         return InlineFlowBox::logicalTopLayoutOverflow(lineTop());
     }
     LayoutUnit logicalBottomLayoutOverflow() const
     {
         return InlineFlowBox::logicalBottomLayoutOverflow(lineBottom());
     }
 
-#if ENABLE(CSS3_TEXT)
     // Used to calculate the underline offset for TextUnderlinePositionUnder.
     float maxLogicalTop() const { return m_maxLogicalTop; }
-#endif // CSS3_TEXT
 
     Node* getLogicalStartBoxWithNode(InlineBox*&) const;
     Node* getLogicalEndBoxWithNode(InlineBox*&) const;
 
 #ifndef NDEBUG
     virtual const char* boxName() const;
 #endif
 private:
     LayoutUnit lineSnapAdjustment(LayoutUnit delta = 0) const;
 
@@ skipping 15 matching lines @@
     // we can create an InlineIterator beginning just after the end of this line.
     RenderObject* m_lineBreakObj;
     RefPtr<BidiContext> m_lineBreakContext;
 
     LayoutUnit m_lineTop;
     LayoutUnit m_lineBottom;
 
     LayoutUnit m_lineTopWithLeading;
     LayoutUnit m_lineBottomWithLeading;
 
-#if ENABLE(CSS3_TEXT)
     // Maximum logicalTop among all children of an InlineFlowBox. Used to
     // calculate the offset for TextUnderlinePositionUnder.
     float m_maxLogicalTop;

[eseidel, 2013/05/10 17:31:40]

So every Linebox now gets 4 bytes bigger, eh?  That could be a lot of memory.

[bruno.abinader, 2013/05/10 18:23:14]

Lamarque (my colleague who implemented text-underline-position) said he could
modify the code to have this calculated for each RootInlineIndex instead of
simply storing the value. However, we'd be exchanging memory footpring for extra
processing.

-#endif // CSS3_TEXT
 
     struct LineFragmentationData {
         WTF_MAKE_NONCOPYABLE(LineFragmentationData); WTF_MAKE_FAST_ALLOCATED;
     public:
         LineFragmentationData()
             : m_containingRegion(0)
             , m_paginationStrut(0)
             , m_paginatedLineWidth(0)
             , m_isFirstAfterPageBreak(false)
         {
@@ skipping 11 matching lines @@
     OwnPtr<LineFragmentationData> m_fragmentationData;
 
     // Floats hanging off the line are pushed into this vector during layout. It is only
     // good for as long as the line has not been marked dirty.
     OwnPtr<Vector<RenderBox*> > m_floats;
 };
 
 } // namespace WebCore
 
 #endif // RootInlineBox_h