Use smart pointers for class owned pointers

fpdfsdk/javascript/cjs_context.h

 // Copyright 2014 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.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef FPDFSDK_JAVASCRIPT_CJS_CONTEXT_H_
 #define FPDFSDK_JAVASCRIPT_CJS_CONTEXT_H_
 
+#include <memory>
+
 #include "core/fxcrt/include/fx_string.h"
 #include "core/fxcrt/include/fx_system.h"
 #include "fpdfsdk/javascript/ijs_context.h"
 
 class CJS_EventHandler;
 class CJS_Runtime;
 class CPDFDoc_Environment;
 
 class CJS_Context : public IJS_Context {
  public:
@@ skipping 94 matching lines @@
                         CPDFSDK_Annot* pScreen) override;
   void OnBookmark_MouseUp(CPDF_Bookmark* pBookMark) override;
   void OnLink_MouseUp(CPDFSDK_Document* pTarget) override;
   void OnMenu_Exec(CPDFSDK_Document* pTarget,
                    const CFX_WideString& strTargetName) override;
   void OnBatchExec(CPDFSDK_Document* pTarget) override;
   void OnConsole_Exec() override;
   void OnExternal_Exec() override;
 
   CJS_Runtime* GetJSRuntime() const { return m_pRuntime; }
-  CJS_EventHandler* GetEventHandler() const { return m_pEventHandler; }
+  CJS_EventHandler* GetEventHandler() const { return m_pEventHandler.get(); }
 
   CPDFDoc_Environment* GetReaderApp();
   CPDFSDK_Document* GetReaderDocument();
 
  private:
-  CJS_Runtime* m_pRuntime;
-  CJS_EventHandler* m_pEventHandler;
+  CJS_Runtime* const m_pRuntime;
+  std::unique_ptr<CJS_EventHandler> m_pEventHandler;
   FX_BOOL m_bBusy;
 };
 
 #endif  // FPDFSDK_JAVASCRIPT_CJS_CONTEXT_H_