Avoid layout/full-repaint on view height change if possible

Source/core/rendering/RenderView.h

Index: Source/core/rendering/RenderView.h
diff --git a/Source/core/rendering/RenderView.h b/Source/core/rendering/RenderView.h
index b2e8d30f1e1dbac342dc4c5284c28f981846a734..6de6e94d9c1517c3568a27d8216015bf7343ec21 100644
--- a/Source/core/rendering/RenderView.h
+++ b/Source/core/rendering/RenderView.h
@@ -206,6 +206,8 @@ public:
     double layoutViewportWidth() const;
     double layoutViewportHeight() const;
 
+    void viewResized();
+
 private:
     virtual void mapLocalToContainer(const RenderLayerModelObject* repaintContainer, TransformState&, MapCoordinatesFlags = ApplyContainerFlip, bool* wasFixed = 0) const OVERRIDE;
     virtual const RenderObject* pushMappingToContainer(const RenderLayerModelObject* ancestorToStopAt, RenderGeometryMap&) const OVERRIDE;
@@ -272,6 +274,8 @@ private:
 
     bool shouldUsePrintingLayout() const;
 
+    bool needsLayoutOnLogicalHeightChange() const;
+
     FrameView* m_frameView;
 
     RenderObject* m_selectionStart;