add portable and canonical font support for DM

tools/sk_tool_utils.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 sk_tool_utils_DEFINED
 #define sk_tool_utils_DEFINED
 
-#include "SkBitmap.h"
-#include "SkCanvas.h"
 #include "SkImageInfo.h"
-#include "SkPaint.h"
 #include "SkTypeface.h"
 
+class SkBitmap;
+class SkCanvas;
+class SkPaint;
+class SkTestFont;
+
 namespace sk_tool_utils {
 
-    extern bool gEnablePortableTypeface;
-
     const char* colortype_name(SkColorType);
 
     /**
      * Sets the paint to use a platform-independent text renderer.
      */
-    void set_portable_typeface(SkPaint* paint, SkTypeface::Style style = SkTypeface::kNormal);
+    void set_portable_typeface(SkPaint* paint, const char* name = NULL,
+                               SkTypeface::Style style = SkTypeface::kNormal);
+    SkTypeface* create_portable_typeface(const char* name, SkTypeface::Style style);
+    void report_used_chars();
 
     /**
      *  Call canvas->writePixels() by using the pixels from bitmap, but with an info that claims
      *  the pixels are colorType + alphaType
      */
     void write_pixels(SkCanvas*, const SkBitmap&, int x, int y, SkColorType, SkAlphaType);
 
+    // private to sk_tool_utils
+    SkTypeface* create_font(const char* name, SkTypeface::Style );
+    SkTypeface* resource_font(const char* name, SkTypeface::Style );
+
 }  // namespace sk_tool_utils
 
 #endif  // sk_tool_utils_DEFINED