Extend SkFontMgr_Custom to cover ttc, otf, pfb.

src/ports/SkFontHost_FreeType_common.h

 /*
  * Copyright 2006-2012 The Android Open Source Project
  * Copyright 2012 Mozilla Foundation
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SKFONTHOST_FREETYPE_COMMON_H_
 #define SKFONTHOST_FREETYPE_COMMON_H_
 
 #include "SkGlyph.h"
 #include "SkScalerContext.h"
 #include "SkTypeface.h"
+#include "SkTypes.h"
 
 #include <ft2build.h>
 #include FT_FREETYPE_H
 
 #ifdef SK_DEBUG
     #define SkASSERT_CONTINUE(pred)                                                         \
         do {                                                                                \
             if (!(pred))                                                                    \
                 SkDebugf("file %s:%d: assert failed '" #pred "'\n", __FILE__, __LINE__);    \
         } while (false)
@@ skipping 16 matching lines @@
 
 private:
     typedef SkScalerContext INHERITED;
 };
 
 class SkTypeface_FreeType : public SkTypeface {
 public:
     /** For SkFontMgrs to make use of our ability to extract
      *  name and style from a stream, using FreeType's API.
      */
-    static bool ScanFont(SkStream* stream, int ttcIndex,
-                         SkString* name, SkFontStyle* style, bool* isFixedPitch);
+    class Scanner : ::SkNoncopyable {
+    public:
+        Scanner();
+        ~Scanner();
+        bool recognizedFont(SkStream* stream, int* numFonts) const;
+        bool scanFont(SkStream* stream, int ttcIndex,
+                      SkString* name, SkFontStyle* style, bool* isFixedPitch) const;
+    private:
+        FT_Face openFace(SkStream* stream, int ttcIndex, FT_Stream ftStream) const;
+        FT_Library fLibrary;
+        mutable SkMutex fLibraryMutex;
+    };
 
 protected:
     SkTypeface_FreeType(const SkFontStyle& style, SkFontID uniqueID, bool isFixedPitch)
         : INHERITED(style, uniqueID, isFixedPitch)
         , fGlyphCount(-1)
     {}
 
     virtual SkScalerContext* onCreateScalerContext(
                                         const SkDescriptor*) const SK_OVERRIDE;
     virtual void onFilterRec(SkScalerContextRec*) const SK_OVERRIDE;
@@ skipping 13 matching lines @@
     virtual size_t onGetTableData(SkFontTableTag, size_t offset,
                                   size_t length, void* data) const SK_OVERRIDE;
 
 private:
     mutable int fGlyphCount;
 
     typedef SkTypeface INHERITED;
 };
 
 #endif // SKFONTHOST_FREETYPE_COMMON_H_