Add infrastructure for partial layouts

Source/core/rendering/RenderListBox.h

 /*
  * This file is part of the select element renderer in WebCore.
  *
  * Copyright (C) 2006, 2007, 2009 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
@@ skipping 63 matching lines @@
 
     virtual bool scrollImpl(ScrollDirection, ScrollGranularity, float) OVERRIDE;
 
     virtual void computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const OVERRIDE;
     virtual void computePreferredLogicalWidths() OVERRIDE;
     virtual int baselinePosition(FontBaseline, bool firstLine, LineDirectionMode, LinePositionMode = PositionOnContainingLine) const;
     virtual void computeLogicalHeight(LayoutUnit logicalHeight, LayoutUnit logicalTop, LogicalExtentComputedValues&) const OVERRIDE;
 
     virtual void layout();
 
+    virtual bool supportsPartialLayout() const OVERRIDE { return false; }
+
     virtual void addFocusRingRects(Vector<IntRect>&, const LayoutPoint& additionalOffset, const RenderLayerModelObject* paintContainer = 0) OVERRIDE;
 
     virtual bool canBeProgramaticallyScrolled() const { return true; }
     virtual void autoscroll(const IntPoint&);
     virtual void stopAutoscroll();
 
     virtual bool shouldPanScroll() const { return true; }
     virtual void panScroll(const IntPoint&);
 
     virtual int verticalScrollbarWidth() const;
@@ skipping 68 matching lines @@
     ASSERT_WITH_SECURITY_IMPLICATION(!object || object->isListBox());
     return static_cast<RenderListBox*>(object);
 }
 
 // This will catch anyone doing an unnecessary cast.
 void toRenderListBox(const RenderListBox*);
 
 } // namepace WebCore
 
 #endif // RenderListBox_h