Revert of Fix race condition in parallel font initialization.

include/ports/SkFontConfigInterface.h

Index: include/ports/SkFontConfigInterface.h
diff --git a/include/ports/SkFontConfigInterface.h b/include/ports/SkFontConfigInterface.h
index f548f37d5d2a340015555d1dcf15eab611811957..8c12a5628ad05bf9e2ef625f7f7d53921474de10 100644
--- a/include/ports/SkFontConfigInterface.h
+++ b/include/ports/SkFontConfigInterface.h
@@ -13,8 +13,6 @@
 #include "SkRefCnt.h"
 #include "SkTArray.h"
 #include "SkTypeface.h"
-
-struct SkBaseMutex;
 
 /**
  *  \class SkFontConfigInterface
@@ -97,9 +95,8 @@
     /**
      *  Return a singleton instance of a direct subclass that calls into
      *  libfontconfig. This does not affect the refcnt of the returned instance.
-     *  The mutex may be used to guarantee the singleton is only constructed once.
      */
-    static SkFontConfigInterface* GetSingletonDirectInterface(SkBaseMutex* mutex);
+    static SkFontConfigInterface* GetSingletonDirectInterface();
 
     // New APIS, which have default impls for now (which do nothing)