text-overflow on button should have effect

Source/core/rendering/RenderButton.h

 /*
  * Copyright (C) 2005 Apple Computer
  *
  * 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 22 matching lines @@
 // to date as the button changes.
 class RenderButton FINAL : public RenderFlexibleBox {
 public:
     explicit RenderButton(Element*);
     virtual ~RenderButton();
 
     virtual const char* renderName() const OVERRIDE { return "RenderButton"; }
     virtual bool isRenderButton() const OVERRIDE { return true; }
 
     virtual bool canBeSelectionLeaf() const OVERRIDE { return node() && node()->rendererIsEditable(); }
+    virtual bool canCollapseAnonymousBlockChild() const OVERRIDE { return true; }
 
     virtual void addChild(RenderObject* newChild, RenderObject *beforeChild = 0) OVERRIDE;
     virtual void removeChild(RenderObject*) OVERRIDE;
     virtual void removeLeftoverAnonymousBlock(RenderBlock*) OVERRIDE { }
     virtual bool createsAnonymousWrapper() const OVERRIDE { return true; }
 
     void setupInnerStyle(RenderStyle*);
 
     // <button> should allow whitespace even though RenderFlexibleBox doesn't.
     virtual bool canHaveWhitespaceChildren() const OVERRIDE { return true; }
@@ skipping 11 matching lines @@
     virtual bool hasLineIfEmpty() const OVERRIDE { return node() && node()->hasTagName(HTMLNames::inputTag); }
 
     RenderBlock* m_inner;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderButton, isRenderButton());
 
 } // namespace WebCore
 
 #endif // RenderButton_h