Add infrastructure for partial layouts

Source/core/rendering/RenderTextControl.h

Index: Source/core/rendering/RenderTextControl.h
diff --git a/Source/core/rendering/RenderTextControl.h b/Source/core/rendering/RenderTextControl.h
index 426c369a976829571defdbcb883a5ca9fb30bee3..607f421f9c3a6f6d8f130ddfdecaf87bd27fe65e 100644
--- a/Source/core/rendering/RenderTextControl.h
+++ b/Source/core/rendering/RenderTextControl.h
@@ -67,6 +67,7 @@ protected:
 private:
     virtual const char* renderName() const { return "RenderTextControl"; }
     virtual bool isTextControl() const { return true; }
+    virtual bool supportsPartialLayout() const OVERRIDE { return false; }
     virtual void computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const OVERRIDE;
     virtual void computePreferredLogicalWidths() OVERRIDE;
     virtual void removeLeftoverAnonymousBlock(RenderBlock*) { }
@@ -113,7 +114,7 @@ public:
     }
     virtual int firstLineBoxBaseline() const OVERRIDE { return RenderBlock::firstLineBoxBaseline(); }
     virtual int inlineBlockBaseline(LineDirectionMode direction) const OVERRIDE { return lastLineBoxBaseline(direction); }
-
+    virtual bool supportsPartialLayout() const OVERRIDE { return false; }
 };