Remove obsolete Mac flipped coordinates comment.

third_party/WebKit/Source/platform/Widget.h

 /*
  * Copyright (C) 2004, 2005, 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2008 Collabora Ltd.  All rights reserved.
  * Copyright (C) 2013 Google 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
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 74 matching lines @@
     virtual bool isPluginView() const { return false; }
     virtual bool isPluginContainer() const { return false; }
     virtual bool isScrollbar() const { return false; }
 
     virtual void setParent(Widget*);
     Widget* parent() const { return m_parent; }
     Widget* root() const;
 
     virtual void handleEvent(Event*) { }
 
-    // It is important for cross-platform code to realize that Mac has flipped coordinates. Therefore any code
-    // that tries to convert the location of a rect using the point-based convertFromRootFrame will end
-    // up with an inaccurate rect. Always make sure to use the rect-based convertFromRootFrame method
-    // when converting window rects.
     IntRect convertToRootFrame(const IntRect&) const;
     IntRect convertFromRootFrame(const IntRect&) const;
 
     IntPoint convertToRootFrame(const IntPoint&) const;
     IntPoint convertFromRootFrame(const IntPoint&) const;
     FloatPoint convertFromRootFrame(const FloatPoint&) const;
 
     virtual void frameRectsChanged() { }
 
     virtual void widgetGeometryMayHaveChanged() { }
@@ skipping 16 matching lines @@
 private:
     Member<Widget> m_parent;
     IntRect m_frame;
     bool m_selfVisible;
     bool m_parentVisible;
 };
 
 } // namespace blink
 
 #endif // Widget_h