Fix under-invalidation of frameset on resize

third_party/WebKit/Source/core/layout/LayoutFrameSet.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Simon Hausmann <hausmann@kde.org>
  * Copyright (C) 2006, 2008 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 121 matching lines @@
   void computeEdgeInfo();
   void fillFromEdgeInfo(const FrameEdgeInfo&, int r, int c);
   void positionFrames();
 
   int splitPosition(const GridAxis&, int split) const;
   int hitTestSplit(const GridAxis&, int position) const;
 
   void startResizing(GridAxis&, int position);
   void continueResizing(GridAxis&, int position);
 
+  bool paintedOutputOfObjectHasNoEffectRegardlessOfSize() const override {
+    return false;
+  }
+
   LayoutObjectChildList m_children;
 
   GridAxis m_rows;
   GridAxis m_cols;
 
   bool m_isResizing;
   bool m_isChildResizing;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutFrameSet, isFrameSet());
 
 }  // namespace blink
 
 #endif  // LayoutFrameSet_h