Make DOMSelection cache Range

third_party/WebKit/Source/core/editing/SelectionEditor.h

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple 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.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 64 matching lines @@
   Range* firstRange() const;
 
   // There functions are exposed for |FrameSelection|.
   void resetLogicalRange();
   void setLogicalRange(Range*);
 
   // Updates |m_selection| and |m_selectionInFlatTree| with up-to-date
   // layout if needed.
   void updateIfNeeded();
 
+  void cacheRangeOfDocument(Range*);
+  Range* documentCachedRange() const;
+  void clearDocumentCachedRange();
+
   DECLARE_TRACE();
 
  private:
   explicit SelectionEditor(LocalFrame&);
 
   const Document& document() const;
   LocalFrame* frame() const { return m_frame.get(); }
 
   void clearVisibleSelection();
   bool shouldAlwaysUseDirectionalSelection() const;
 
   Member<Document> m_document;
   Member<LocalFrame> m_frame;
 
   VisibleSelection m_selection;
   VisibleSelectionInFlatTree m_selectionInFlatTree;
   bool m_observingVisibleSelection;
 
+  // TODO(editing-dev): Removing |m_logicalRange|
   // The range specified by the user, which may not be visually canonicalized
   // (hence "logical"). This will be invalidated if the underlying
   // |VisibleSelection| changes. If that happens, this variable will
   // become |nullptr|, in which case logical positions == visible positions.
   Member<Range> m_logicalRange;
+  // If document is root, document.getSelection().addRange(range) is cached on
+  // this.
+  Member<Range> m_cachedRange;
 };
 
 }  // namespace blink
 
 #endif  // SelectionEditor_h