Fix thread unsafe mutex initialization.

src/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
 
@@ skipping 56 matching lines @@
 
 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) \
-    static inline void SK_MACRO_APPEND_LINE(name)(){} \
-    static SkBaseMutex name
+#define SK_DECLARE_STATIC_MUTEX(name) namespace{} static SkBaseMutex name
 
 #endif