Re-land "Rename CFWL_Thread classes to ThreadImp"

xfa/include/fwl/core/fwl_thread.h

Index: xfa/include/fwl/core/fwl_thread.h
diff --git a/xfa/include/fwl/core/fwl_thread.h b/xfa/include/fwl/core/fwl_thread.h
index 3bc5c3c289cb01c6dedf9a3afeedd9065a76094f..ed1fd9fc433e1f3396dca94452a0b49859d97276 100644
--- a/xfa/include/fwl/core/fwl_thread.h
+++ b/xfa/include/fwl/core/fwl_thread.h
@@ -4,47 +4,48 @@
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
-#ifndef _FWL_THREAD_H
-#define _FWL_THREAD_H
+#ifndef FWL_THREAD_H_
+#define FWL_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
+//                                   |                       |
+//      (nonesuch)              IFWL_NoteThread         CFWL_NoteThreadImp
+//                                   |                       |
+//                                   A                       A
+//                m_pIface           |                       |
+//      CFWL_App --------------> IFWL_App                CFWL_AppImp
+//
+
+class CFWL_ThreadImp;
 class IFWL_NoteDriver;
-class IFWL_Thread;
-class IFWL_NoteThread;
+
 typedef struct _FWL_HTHREAD { void* pData; } * FWL_HTHREAD;
+
 class IFWL_Thread {
  public:
-  static IFWL_Thread* Create();
+  // These call into polymorphic methods in the impl; no need to override.
+  void Release();
+  FWL_ERR Run(FWL_HTHREAD hThread);
+
+  CFWL_ThreadImp* GetImpl() const { return m_pImpl; }
+  void SetImpl(CFWL_ThreadImp* pImpl) { m_pImpl = pImpl; }
 
  protected:
   virtual ~IFWL_Thread() {}
 
- public:
-  virtual void Release() = 0;
-  virtual FWL_ERR Run(FWL_HTHREAD hThread) = 0;
+ private:
+  CFWL_ThreadImp* m_pImpl;
 };
-FWL_HTHREAD FWL_StartThread(IFWL_Thread* pThread, FX_BOOL bSuspended = FALSE);
-FWL_ERR FWL_ResumeThread(FWL_HTHREAD hThread);
-FWL_ERR FWL_SuspendThread(FWL_HTHREAD hThread);
-FWL_ERR FWL_KillThread(FWL_HTHREAD hThread, int32_t iExitCode);
-FWL_ERR FWL_StopThread(FWL_HTHREAD hThread, int32_t iExitCode);
-FWL_ERR FWL_Sleep(FX_DWORD dwMilliseconds);
+
 class IFWL_NoteThread : public IFWL_Thread {
  public:
-  static IFWL_NoteThread* Create();
-  virtual FWL_ERR Run(FWL_HTHREAD hThread) = 0;
-  virtual IFWL_NoteDriver* GetNoteDriver() = 0;
+  IFWL_NoteDriver* GetNoteDriver();
 };
-typedef struct _FWL_HMUTEX { void* pData; } * FWL_HMUTEX;
-FWL_HMUTEX FWL_CreateMutex();
-FWL_ERR FWL_DestroyMutex(FWL_HMUTEX hMutex);
-FWL_ERR FWL_LockMutex(FWL_HMUTEX hMutex);
-FWL_ERR FWL_TryLockMutex(FWL_HMUTEX hMutex);
-FWL_ERR FWL_UnlockMutex(FWL_HMUTEX hMutex);
-FWL_ERR FWL_IsLockedMutex(FWL_HMUTEX hMutex, FX_BOOL& bLocked);
-typedef struct _FWL_HSEMAPHORE { void* pData; } * FWL_HSEMAPHORE;
-FWL_HSEMAPHORE FWL_CreateSemaphore();
-FWL_ERR FWL_DestroySemaphore(FWL_HSEMAPHORE hSemaphore);
-FWL_ERR FWL_WaitSemaphore(FWL_HSEMAPHORE hSemaphore);
-FWL_ERR FWL_PostSemaphore(FWL_HSEMAPHORE hSemaphore, int32_t down = 1);
-FWL_ERR FWL_GetSemaphoreValue(FWL_HSEMAPHORE hSemaphore, int32_t& value);
-FWL_ERR FWL_ResetSemaphore(FWL_HSEMAPHORE hSemaphore, int32_t init);
-#endif
+
+#endif  // FWL_THREAD_H_