Merge IFWL_App and FWL_AppImp together

xfa/fwl/core/fwl_appimp.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 XFA_FWL_CORE_FWL_APPIMP_H_
-#define XFA_FWL_CORE_FWL_APPIMP_H_
-
-#include <memory>
-
-#include "xfa/fwl/core/fwl_noteimp.h"
-
-class CFWL_WidgetMgr;
-class CXFA_FFApp;
-class IFWL_App;
-class IFWL_NoteThread;
-class IFWL_ThemeProvider;
-
-class CFWL_AppImp {
- public:
-  CFWL_AppImp(IFWL_App* pIface, CXFA_FFApp* pAdapter);
-  ~CFWL_AppImp();
-
-  IFWL_App* GetInterface() const { return m_pIface; }
-  CFWL_NoteDriver* GetNoteDriver() const { return m_pNoteDriver.get(); }
-
-  FWL_Error Initialize();
-  FWL_Error Finalize();
-  CXFA_FFApp* GetAdapterNative() const;
-  CFWL_WidgetMgr* GetWidgetMgr() const;
-  IFWL_ThemeProvider* GetThemeProvider() const;
-  void SetThemeProvider(IFWL_ThemeProvider* pThemeProvider);
-  void Exit(int32_t iExitCode);
-
- private:
-  CXFA_FFApp* const m_pAdapterNative;
-  std::unique_ptr<CFWL_WidgetMgr> m_pWidgetMgr;
-  IFWL_ThemeProvider* m_pThemeProvider;
-  std::unique_ptr<CFWL_NoteDriver> m_pNoteDriver;
-  IFWL_App* const m_pIface;
-};
-
-#endif  // XFA_FWL_CORE_FWL_APPIMP_H_