Oilpan: Prepare moving InspectorController and InspectorAgents to oilpan.

Source/core/inspector/InspectorBaseAgent.h

 /*
  * Copyright (C) 2011 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef InspectorBaseAgent_h
 #define InspectorBaseAgent_h
 
 #include "InspectorBackendDispatcher.h"
+#include "core/inspector/InstrumentingAgents.h"
+#include "platform/heap/Handle.h"
 #include "wtf/Forward.h"
 #include "wtf/Vector.h"
 #include "wtf/text/WTFString.h"
 
 namespace WebCore {
 
 class InspectorFrontend;
 class InspectorCompositeState;
 class InspectorState;
 class InstrumentingAgents;
 
-class InspectorAgent {
+class InspectorAgent : public NoBaseWillBeGarbageCollectedFinalized<InspectorAgent> {
 public:
     explicit InspectorAgent(const String&);
     virtual ~InspectorAgent();
+    virtual void trace(Visitor*);

[haraken, 2014/06/12 05:53:00]

Add OVERRIDE.

[keishi, 2014/06/13 03:37:33]

This is the base class.

 
     virtual void init() { }
     virtual void setFrontend(InspectorFrontend*) { }
     virtual void clearFrontend() { }
     virtual void restore() { }
     virtual void registerInDispatcher(InspectorBackendDispatcher*) = 0;
     virtual void discardAgent() { }
     virtual void didCommitLoadForMainFrame() { }
     virtual void flushPendingFrontendMessages() { }
 
     String name() { return m_name; }
     void appended(InstrumentingAgents*, InspectorState*);
 
 protected:
-    InstrumentingAgents* m_instrumentingAgents;
+    RawPtrWillBeMember<InstrumentingAgents> m_instrumentingAgents;
     InspectorState* m_state;

[haraken, 2014/06/12 05:53:00]

This raw pointer looks safe because InspectorCompositeState::m_inspectorStateMap
keeps the InspectorState alive while InspectorAgent holds the InspectorState.

However, the lifetime relationship is complicated, so it would be better to move
InspectorState to the heap.

Shall we add a FIXME and address in a follow-up?

[keishi, 2014/06/13 03:37:33]

Done.

 
 private:
     String m_name;
 };
 
-class InspectorAgentRegistry {
+class InspectorAgentRegistry : public NoBaseWillBeGarbageCollectedFinalized<InspectorAgentRegistry> {

[haraken, 2014/06/12 05:53:00]

Add FINAL.

[keishi, 2014/06/13 03:37:32]

Done.

 public:
     InspectorAgentRegistry(InstrumentingAgents*, InspectorCompositeState*);
-    void append(PassOwnPtr<InspectorAgent>);
+    void append(PassOwnPtrWillBeRawPtr<InspectorAgent>);
 
     void setFrontend(InspectorFrontend*);
     void clearFrontend();
     void restore();
     void registerInDispatcher(InspectorBackendDispatcher*);
     void discardAgents();
     void flushPendingFrontendMessages();
 
+    void trace(Visitor*);
+
 private:
-    InstrumentingAgents* m_instrumentingAgents;
+    RawPtrWillBeMember<InstrumentingAgents> m_instrumentingAgents;
     InspectorCompositeState* m_inspectorState;

[keishi, 2014/06/11 14:10:53]

SAFE: InspectorAgentRegistry and InspectorCompositeState are owned by
InspectorController so they die together.

[haraken, 2014/06/12 05:53:00]

I agree that this is safe, but it would be better to move
InspectorCompositeState to the heap. If someone (other than InspectorController)
starts holding a Member to InspectorAgentRegistry in the future, there is no
guarantee that the InspectorAgentRegistry and the InspectorCompositeState die
together. Then m_inspectorState can be a stale pointer.

Shall we add a FIXME and address in a follow-up?

[keishi, 2014/06/13 03:37:33]

Done.

-    Vector<OwnPtr<InspectorAgent> > m_agents;
+    WillBeHeapVector<OwnPtrWillBeMember<InspectorAgent> > m_agents;
 };
 
 template<typename T>
 class InspectorBaseAgent : public InspectorAgent {
 public:
     virtual ~InspectorBaseAgent() { }
 
     virtual void registerInDispatcher(InspectorBackendDispatcher* dispatcher) OVERRIDE FINAL
     {
         dispatcher->registerAgent(static_cast<T*>(this));
     }
 
 protected:
     InspectorBaseAgent(const String& name) : InspectorAgent(name)
     {
     }
 };
 
 } // namespace WebCore
 
 #endif // !defined(InspectorBaseAgent_h)