make gm background colors 565 compatible

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 "SkColor.h"
 #include "SkImageEncoder.h"
 #include "SkImageInfo.h"
 #include "SkPixelSerializer.h"
 #include "SkTypeface.h"
 
 class SkBitmap;
 class SkCanvas;
 class SkPaint;
 class SkShader;
 class SkTestFont;
 class SkTextBlobBuilder;
 
 namespace sk_tool_utils {
 
     const char* colortype_name(SkColorType);
-    void color_to_565(SkColor* color);
+    SkColor color_to_565(SkColor color);
 
     /**
      * Sets the paint to use a platform-independent text renderer if FLAGS_portableFonts is set.
      * FIXME: will become obsolete as GMs migrate to set portable typeface always.
      */
     void set_portable_typeface(SkPaint* paint, const char* name = NULL,
                                SkTypeface::Style style = SkTypeface::kNormal);
     void set_portable_typeface_always(SkPaint* paint, const char* name = NULL,
                                SkTypeface::Style style = SkTypeface::kNormal);
     SkTypeface* create_portable_typeface(const char* name, SkTypeface::Style style);
@@ skipping 37 matching lines @@
         }
     };
 
     // A helper for inserting a drawtext call into a SkTextBlobBuilder
     void add_to_text_blob(SkTextBlobBuilder* builder, const char* text, const SkPaint& origPaint,
                           SkScalar x, SkScalar y);
 
 }  // namespace sk_tool_utils
 
 #endif  // sk_tool_utils_DEFINED