support SK_FONTHOST_USES_FONTMGR on mac

src/fonts/SkGScalerContext.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGScalerContext.h"
 #include "SkGlyph.h"
 #include "SkPath.h"
@@ skipping 193 matching lines @@
 
 int SkGTypeface::onGetTableTags(SkFontTableTag tags[]) const {
     return fProxy->getTableTags(tags);
 }
 
 size_t SkGTypeface::onGetTableData(SkFontTableTag tag, size_t offset,
                                     size_t length, void* data) const {
     return fProxy->getTableData(tag, offset, length, data);
 }
 
+SkTypeface* SkGTypeface::onRefMatchingStyle(Style style) const {
+    if (this->style() == style) {
+        return const_cast<SkGTypeface*>(SkRef(this));
+    }
+
+    SkAutoTUnref<SkTypeface> other(fProxy->refMatchingStyle(style));
+    return SkNEW_ARGS(SkGTypeface, (other, fPaint));
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 #if 0
 // under construction -- defining a font purely in terms of skia primitives
 // ala an SVG-font.
 class SkGFont : public SkRefCnt {
 public:
     virtual ~SkGFont();
 
     int unicharToGlyph(SkUnichar) const;
@@ skipping 21 matching lines @@
 
     friend class SkGFontBuilder;
     SkGFont(int count, Glyph* array);
 };
 
 class SkGFontBuilder {
 public:
 
 };
 #endif