Cleanup in webkit/glue/

webkit/glue/image_decoder.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/basictypes.h"
 #include "base/gfx/size.h"
 #include "base/scoped_ptr.h"
 
 class SkBitmap;
 
 namespace webkit_glue {
 
 // Provides an interface to WebKit's image decoders.
 //
 // Note to future: This class should be deleted. We should have our own nice
 // image decoders in base/gfx, and our port should use those. Currently, it's
 // the other way around.
 class ImageDecoder {
  public:
   // Use the constructor with desired_size when you think you may have an .ico
   // format and care about which size you get back. Otherwise, use the 0-arg
   // constructor.
   ImageDecoder();
   ImageDecoder(const gfx::Size& desired_icon_size);
   ~ImageDecoder();
 
   // Call this function to decode the image. If successful, the decoded image
   // will be returned. Otherwise, an empty bitmap will be returned.
-  SkBitmap Decode(const unsigned char* data, size_t size);
+  SkBitmap Decode(const unsigned char* data, size_t size) const;
 
  private:
   // Size will be empty to get the largest possible size.
   gfx::Size desired_icon_size_;
 
   DISALLOW_EVIL_CONSTRUCTORS(ImageDecoder);
 };
 
 }  // namespace webkit_glue