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* 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 );

[mtklein, 2014/07/30 15:03:57]

Given how much shorter sk_tool_utils_font.cpp has now become, why not merge all
that back into sk_tool_utils.cpp and make these two static?

[caryclark, 2014/07/30 15:45:32]

It's going to get longer soon. The next step is to create SkFontMgr child
classes, one for portable fonts and one for resource fonts. These functions will
go away and become SkFontMgr::createLegacyTypeface implementations. This is
gated by some rewriting underway that will allow more than one SkFontMgr at a
time.

+    SkTypeface* resource_font(const char* name, SkTypeface::Style );
+
+    void release_portable_typeface();
+
 }  // namespace sk_tool_utils
 
 #endif  // sk_tool_utils_DEFINED