More FWL interface cleanup.

xfa/fwl/core/ifwl_thread.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_IFWL_THREAD_H_
-#define XFA_FWL_CORE_IFWL_THREAD_H_
-
-// The FWL thread/app code contains three parallel inheritance hierarchies,
-// which reference each other via pointers as follows:
-//
-//                                           m_pImpl
-//      (nonesuch)              IFWL_Thread ----------> CFWL_ThreadImp
-//                                   |      <----------      |
-//                                   A       m_pIface        A
-//                m_pIface           |                       |
-//      CXFA_FFApp ------------> IFWL_App                CFWL_AppImp
-//
-
-#include "xfa/fwl/core/fwl_error.h"
-
-class CFWL_ThreadImp;
-class IFWL_NoteDriver;
-
-class IFWL_Thread {
- public:
-  // These call into polymorphic methods in the impl; no need to override.
-  void Release();
-
-  CFWL_ThreadImp* GetImpl() const { return m_pImpl; }
-  void SetImpl(CFWL_ThreadImp* pImpl) { m_pImpl = pImpl; }
-
-  IFWL_NoteDriver* GetNoteDriver() const;
-
- protected:
-  virtual ~IFWL_Thread() {}
-
- private:
-  CFWL_ThreadImp* m_pImpl;
-};
-
-#endif  // XFA_FWL_CORE_IFWL_THREAD_H_