ResizeObserver implementation, part 2: lifetime

third_party/WebKit/Source/core/observer/ResizeObserver.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ResizeObserver_h
 #define ResizeObserver_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
 class Document;
 class Element;
 class ResizeObserverCallback;
-class ResizeObserverEntry;
+class ResizeObserverController;
+class ResizeObservation;
 
 // ResizeObserver represents ResizeObserver javascript api:
 // https://github.com/WICG/ResizeObserver/
 class ResizeObserver final : public GarbageCollectedFinalized<ResizeObserver>, public ScriptWrappable {
     DEFINE_WRAPPERTYPEINFO();
 public:
 
     static ResizeObserver* create(Document&, ResizeObserverCallback*);
 
     virtual ~ResizeObserver() {};
 
-
     // API methods
     void observe(Element*);
     void unobserve(Element*);
     void disconnect();
 
     DECLARE_TRACE();
 
 private:
 
+    using ObservationList = HeapLinkedHashSet<WeakMember<ResizeObservation>>;
+
     explicit ResizeObserver(ResizeObserverCallback*, Document&);
 
+    Member<ResizeObserverCallback> m_callback;
+
+    // List of elements we are observing
+    ObservationList m_observations;
+
+    WeakMember<ResizeObserverController> m_controller;
 };
 
 
 } // namespace blink
 
 #endif // ResizeObserver_h