Remove a bit more position:fixed plumbing.

sky/engine/core/rendering/RenderBlock.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 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 215 matching lines @@
 protected:
     virtual void willBeDestroyed() override;
 
     void dirtyForLayoutFromPercentageHeightDescendants(SubtreeLayoutScope&);
 
     virtual void layout() override;
     virtual bool updateImageLoadingPriorities() override final;
 
     enum PositionedLayoutBehavior {
         DefaultLayout,
-        LayoutOnlyFixedPositionedObjects,
         ForcedLayoutAfterContainingBlockMoved
     };
 
     void layoutPositionedObjects(bool relayoutChildren, PositionedLayoutBehavior = DefaultLayout);
-    void markFixedPositionObjectForLayoutIfNeeded(RenderObject* child, SubtreeLayoutScope&);
 
     LayoutUnit marginIntrinsicLogicalWidthForChild(RenderBox* child) const;
 
     int beforeMarginInLineDirection(LineDirectionMode) const;
 
     virtual void paint(PaintInfo&, const LayoutPoint&) override;
     virtual void paintObject(PaintInfo&, const LayoutPoint&) override;
     virtual void paintChildren(PaintInfo&, const LayoutPoint&);
     void paintChild(RenderBox*, PaintInfo&, const LayoutPoint&);
     void paintChildAsInlineBlock(RenderBox*, PaintInfo&, const LayoutPoint&);
@@ skipping 167 matching lines @@
     // FIXME: This is temporary as we move code that accesses block flow
     // member variables out of RenderBlock and into RenderBlockFlow.
     friend class RenderBlockFlow;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderBlock, isRenderBlock());
 
 } // namespace blink
 
 #endif // RenderBlock_h