First pass at removing position:fixed.

sky/engine/core/rendering/ClipRects.h

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 34 matching lines @@
 
     ClipRects()
         : m_refCnt(1)
         , m_fixed(0)
     {
     }
 
     void reset(const LayoutRect& r)
     {
         m_overflowClipRect = r;
-        m_fixedClipRect = r;
         m_posClipRect = r;
         m_fixed = 0;
     }
 
     const ClipRect& overflowClipRect() const { return m_overflowClipRect; }
     void setOverflowClipRect(const ClipRect& r) { m_overflowClipRect = r; }
 
-    const ClipRect& fixedClipRect() const { return m_fixedClipRect; }
-    void setFixedClipRect(const ClipRect&r) { m_fixedClipRect = r; }
-
     const ClipRect& posClipRect() const { return m_posClipRect; }
     void setPosClipRect(const ClipRect& r) { m_posClipRect = r; }
 
     bool fixed() const { return static_cast<bool>(m_fixed); }
     void setFixed(bool fixed) { m_fixed = fixed ? 1 : 0; }
 
     void ref() { m_refCnt++; }
     void deref()
     {
         if (!--m_refCnt)
             delete this;
     }
 
     bool operator==(const ClipRects& other) const
     {
         return m_overflowClipRect == other.overflowClipRect()
-            && m_fixedClipRect == other.fixedClipRect()
             && m_posClipRect == other.posClipRect()
             && fixed() == other.fixed();
     }
 
     ClipRects& operator=(const ClipRects& other)
     {
         m_overflowClipRect = other.overflowClipRect();
-        m_fixedClipRect = other.fixedClipRect();
         m_posClipRect = other.posClipRect();
         m_fixed = other.fixed();
         return *this;
     }
 
 private:
     ClipRects(const LayoutRect& r)
         : m_overflowClipRect(r)
-        , m_fixedClipRect(r)
         , m_posClipRect(r)
         , m_refCnt(1)
         , m_fixed(0)
     {
     }
 
     ClipRects(const ClipRects& other)
         : m_overflowClipRect(other.overflowClipRect())
-        , m_fixedClipRect(other.fixedClipRect())
         , m_posClipRect(other.posClipRect())
         , m_refCnt(1)
         , m_fixed(other.fixed())
     {
     }
 
     ClipRect m_overflowClipRect;
-    ClipRect m_fixedClipRect;
     ClipRect m_posClipRect;
     unsigned m_refCnt : 31;
     unsigned m_fixed : 1;
 };
 
 } // namespace blink
 
 #endif // ClipRects_h