Replace CJS_Runtime::Observer with CFX_Runtime<CJS_Runtime>::Observer

core/fxcrt/include/cfx_observable.h

 // Copyright 2016 PDFium 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 CORE_FXCRT_INCLUDE_CFX_OBSERVABLE_H_
 #define CORE_FXCRT_INCLUDE_CFX_OBSERVABLE_H_
 
 #include <set>
 
 #include "core/fxcrt/include/fx_system.h"
@@ skipping 27 matching lines @@
       m_pWatchedPtr = nullptr;
     }
     Observer& operator=(const Observer& that) = delete;
 
    private:
     T** m_pWatchedPtr;
   };
 
   CFX_Observable() {}
   CFX_Observable(const CFX_Observable& that) = delete;
-  ~CFX_Observable() {
-    for (auto* pObserver : m_Observers)
-      pObserver->OnDestroy();
-  }
+  ~CFX_Observable() { NotifyObservers(); }
   void AddObserver(Observer* pObserver) {
     ASSERT(!pdfium::ContainsKey(m_Observers, pObserver));
     m_Observers.insert(pObserver);
   }
   void RemoveObserver(Observer* pObserver) {
     ASSERT(pdfium::ContainsKey(m_Observers, pObserver));
     m_Observers.erase(pObserver);
   }
+  void NotifyObservers() {
+    for (auto* pObserver : m_Observers)
+      pObserver->OnDestroy();
+    m_Observers.clear();
+  }
   CFX_Observable& operator=(const CFX_Observable& that) = delete;
 
  private:
   std::set<Observer*> m_Observers;
 };
 
 #endif  // CORE_FXCRT_INCLUDE_CFX_OBSERVABLE_H_