Revert of Remove SkThread.h, include SkMutex.h or SkAtomics.h as appropriate.

src/ports/SkFontMgr_win_dw.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkDWrite.h"
 #include "SkDWriteFontFileStream.h"
 #include "SkFontMgr.h"
 #include "SkHRESULT.h"
-#include "SkMutex.h"
 #include "SkStream.h"
 #include "SkTScopedComPtr.h"
+#include "SkThread.h"
 #include "SkTypeface.h"
 #include "SkTypefaceCache.h"
 #include "SkTypeface_win_dw.h"
 #include "SkTypes.h"
 #include "SkUtils.h"
 
 #include <dwrite.h>
 
 #if SK_HAS_DWRITE_2_H
 #include <dwrite_2.h>
@@ skipping 1072 matching lines @@
 }
 
 #include "SkFontMgr_indirect.h"
 SK_API SkFontMgr* SkFontMgr_New_DirectWriteRenderer(SkRemotableFontMgr* proxy) {
     SkAutoTUnref<SkFontMgr> impl(SkFontMgr_New_DirectWrite());
     if (impl.get() == NULL) {
         return NULL;
     }
     return SkNEW_ARGS(SkFontMgr_Indirect, (impl.get(), proxy));
 }