Modernize and trim down SkOnce.

include/ports/SkFontMgr_indirect.h

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkFontMgr_indirect_DEFINED
 #define SkFontMgr_indirect_DEFINED
 
 #include "../private/SkMutex.h"
+#include "../private/SkOnce.h"
 #include "../private/SkTArray.h"
 #include "SkDataTable.h"
 #include "SkFontMgr.h"
 #include "SkRefCnt.h"
 #include "SkRemotableFontMgr.h"
 #include "SkTypeface.h"
 #include "SkTypes.h"
 
 class SkData;
 class SkFontStyle;
 class SkStreamAsset;
 class SkString;
 
 class SK_API SkFontMgr_Indirect : public SkFontMgr {
 public:
     // TODO: The SkFontMgr is only used for createFromStream/File/Data.
     // In the future these calls should be broken out into their own interface
     // with a name like SkFontRenderer.
     SkFontMgr_Indirect(SkFontMgr* impl, SkRemotableFontMgr* proxy)
-        : fImpl(SkRef(impl)), fProxy(SkRef(proxy)), fFamilyNamesInited(false)
+        : fImpl(SkRef(impl)), fProxy(SkRef(proxy))
     { }
 
 protected:
     int onCountFamilies() const override;
     void onGetFamilyName(int index, SkString* familyName) const override;
     SkFontStyleSet* onCreateStyleSet(int index) const override;
 
     SkFontStyleSet* onMatchFamily(const char familyName[]) const override;
 
     SkTypeface* onMatchFamilyStyle(const char familyName[],
@@ skipping 46 matching lines @@
     /**
      *  This cache is essentially { dataId: { ttcIndex: typeface } }
      *  For data caching we want a mapping from data id to weak references to
      *  typefaces with that data id. By storing the index next to the typeface,
      *  this data cache also acts as a typeface cache.
      */
     mutable SkTArray<DataEntry> fDataCache;
     mutable SkMutex fDataCacheMutex;
 
     mutable SkAutoTUnref<SkDataTable> fFamilyNames;
-    mutable bool fFamilyNamesInited;
-    mutable SkMutex fFamilyNamesMutex;
+    mutable SkOnce fFamilyNamesInitOnce;
     static void set_up_family_names(const SkFontMgr_Indirect* self);
 
     friend class SkStyleSet_Indirect;
 };
 
 #endif