Remove the Document.charset setter (making it readonly)

Source/core/html/parser/TextResourceDecoder.h

 /*
     Copyright (C) 1999 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
     Copyright (C) 2006, 2008 Apple Inc. All rights reserved.
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
     version 2 of the License, or (at your option) any later version.
 
@@ skipping 23 matching lines @@
 class CORE_EXPORT TextResourceDecoder {
 public:
     enum EncodingSource {
         DefaultEncoding,
         AutoDetectedEncoding,
         EncodingFromContentSniffing,
         EncodingFromXMLHeader,
         EncodingFromMetaTag,
         EncodingFromCSSCharset,
         EncodingFromHTTPHeader,
-        UserChosenEncoding,
         EncodingFromParentFrame
     };
 
     static PassOwnPtr<TextResourceDecoder> create(const String& mimeType, const WTF::TextEncoding& defaultEncoding = WTF::TextEncoding(), bool usesEncodingDetector = false)
     {
         return adoptPtr(new TextResourceDecoder(mimeType, defaultEncoding, usesEncodingDetector));
     }
     ~TextResourceDecoder();
 
     void setEncoding(const WTF::TextEncoding&, EncodingSource);
@@ skipping 42 matching lines @@
     bool m_useLenientXMLDecoding; // Don't stop on XML decoding errors.
     bool m_sawError;
     bool m_usesEncodingDetector;
 
     OwnPtr<HTMLMetaCharsetParser> m_charsetParser;
 };
 
 }
 
 #endif