Oilpan: move editing objects to the heap.

Source/core/editing/VisibleSelection.h

 /*
  * Copyright (C) 2004 Apple Computer, 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 21 matching lines @@
 
 namespace WebCore {
 
 class LayoutPoint;
 class Position;
 
 const EAffinity SEL_DEFAULT_AFFINITY = DOWNSTREAM;
 enum SelectionDirection { DirectionForward, DirectionBackward, DirectionRight, DirectionLeft };
 
 class VisibleSelection {
+    DISALLOW_ALLOCATION();
 public:
     VisibleSelection();
 
     VisibleSelection(const Position&, EAffinity, bool isDirectional = false);
     VisibleSelection(const Position&, const Position&, EAffinity = SEL_DEFAULT_AFFINITY, bool isDirectional = false);
 
     explicit VisibleSelection(const Range*, EAffinity = SEL_DEFAULT_AFFINITY, bool isDirectional = false);
 
     explicit VisibleSelection(const VisiblePosition&, bool isDirectional = false);
     VisibleSelection(const VisiblePosition&, const VisiblePosition&, bool isDirectional = false);
@@ skipping 69 matching lines @@
     public:
         ChangeObserver();
         virtual ~ChangeObserver();
         virtual void didChangeVisibleSelection() = 0;
     };
 
     void setChangeObserver(ChangeObserver&);
     void clearChangeObserver();
     void didChange(); // Fire the change observer, if any.
 
+    void trace(Visitor*);
+
 #ifndef NDEBUG
     void debugPosition() const;
     void formatForDebugger(char* buffer, unsigned length) const;
     void showTreeForThis() const;
 #endif
 
 private:
     void validate(TextGranularity = CharacterGranularity);
 
     // Support methods for validate()
     void setBaseAndExtentToDeepEquivalents();
     void setStartAndEndFromBaseAndExtentRespectingGranularity(TextGranularity);
     void adjustSelectionToAvoidCrossingShadowBoundaries();
     void adjustSelectionToAvoidCrossingEditingBoundaries();
     void updateSelectionType();
 
     // We need to store these as Positions because VisibleSelection is
     // used to store values in editing commands for use when
     // undoing the command. We need to be able to create a selection that, while currently
     // invalid, will be valid once the changes are undone.
 
     Position m_base;   // Where the first click happened
     Position m_extent; // Where the end click happened
     Position m_start;  // Leftmost position when expanded to respect granularity
     Position m_end;    // Rightmost position when expanded to respect granularity
 
     EAffinity m_affinity;           // the upstream/downstream affinity of the caret
 
+    // Oilpan: this reference has a lifetime that is at least as long
+    // as this object.
     ChangeObserver* m_changeObserver;

[haraken, 2014/05/29 01:14:15]

I agree that no weak processing is needed for the observer.

Given that the only derived class of ChangeObserver is FrameSelection (which is
on heap), can we change this to a Member and trace it? It's not really nice to
leave a raw pointer in on-heap objects.

[sof, 2014/05/29 10:03:53]

Done, made ChangeObserver a GC mixin.

 
     // these are cached, can be recalculated by validate()
     SelectionType m_selectionType; // None, Caret, Range
     bool m_baseIsFirst : 1; // True if base is before the extent
     bool m_isDirectional : 1; // Non-directional ignores m_baseIsFirst and selection always extends on shift + arrow key.
 };
 
 inline bool operator==(const VisibleSelection& a, const VisibleSelection& b)
 {
     return a.start() == b.start() && a.end() == b.end() && a.affinity() == b.affinity() && a.isBaseFirst() == b.isBaseFirst()
         && a.isDirectional() == b.isDirectional();
 }
 
 inline bool operator!=(const VisibleSelection& a, const VisibleSelection& b)
 {
     return !(a == b);
 }
 
 } // namespace WebCore
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 void showTree(const WebCore::VisibleSelection&);
 void showTree(const WebCore::VisibleSelection*);
 #endif
 
 #endif // VisibleSelection_h