Make mutex semaphore based.

include/ports/SkMutex_win.h

-/*
- * Copyright 2013 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#ifndef SkMutex_win_DEFINED
-#define SkMutex_win_DEFINED
-
-/** Windows CriticalSection based mutex. */
-
-#ifndef WIN32_LEAN_AND_MEAN
-#  define WIN32_LEAN_AND_MEAN
-#  define WIN32_IS_MEAN_WAS_LOCALLY_DEFINED
-#endif
-#ifndef NOMINMAX
-#  define NOMINMAX
-#  define NOMINMAX_WAS_LOCALLY_DEFINED
-#endif
-#
-#include <windows.h>
-#
-#ifdef WIN32_IS_MEAN_WAS_LOCALLY_DEFINED
-#  undef WIN32_IS_MEAN_WAS_LOCALLY_DEFINED
-#  undef WIN32_LEAN_AND_MEAN
-#endif
-#ifdef NOMINMAX_WAS_LOCALLY_DEFINED
-#  undef NOMINMAX_WAS_LOCALLY_DEFINED
-#  undef NOMINMAX
-#endif
-
-// On Windows, SkBaseMutex and SkMutex are the same thing,
-// we can't easily get rid of static initializers. However,
-// we preserve the same inheritance pattern as other platforms
-// so that we can forward-declare cleanly.
-struct SkBaseMutex {
-public:
-    SkBaseMutex() {
-        InitializeCriticalSection(&fStorage);
-        SkDEBUGCODE(fOwner = 0;)
-    }
-
-    ~SkBaseMutex() {
-        SkASSERT(0 == fOwner);
-        DeleteCriticalSection(&fStorage);
-    }
-
-    void acquire() {
-        EnterCriticalSection(&fStorage);
-        SkDEBUGCODE(fOwner = GetCurrentThreadId();)
-    }
-
-    void release() {
-        this->assertHeld();
-        SkDEBUGCODE(fOwner = 0;)
-        LeaveCriticalSection(&fStorage);
-    }
-
-    void assertHeld() {
-        SkASSERT(GetCurrentThreadId() == fOwner);
-    }
-
-protected:
-    CRITICAL_SECTION fStorage;
-    SkDEBUGCODE(DWORD fOwner;)
-
-private:
-    SkBaseMutex(const SkBaseMutex&);
-    SkBaseMutex& operator=(const SkBaseMutex&);
-};
-
-class SkMutex : public SkBaseMutex { };
-
-// Windows currently provides no documented means of POD initializing a CRITICAL_SECTION.
-// As a result, it is illegal to SK_DECLARE_STATIC_MUTEX in a function.
-#define SK_DECLARE_STATIC_MUTEX(name) namespace{} static SkBaseMutex name
-
-#endif