Encoding API: Add ignoreBOM flag to decoder options

Source/modules/encoding/TextDecoder.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 36 matching lines @@
     // The replacement encoding is not valid, but the Encoding API also
     // rejects aliases of the replacement encoding.
     if (!encoding.isValid() || !strcasecmp(encoding.name(), "replacement")) {
         exceptionState.throwTypeError("The encoding label provided ('" + encodingLabel + "') is invalid.");
         return 0;
     }
 
     bool fatal = false;
     options.get("fatal", fatal);
 
-    return new TextDecoder(encoding, fatal);
+    bool ignoreBOM = false;
+    options.get("ignoreBOM", ignoreBOM);
+
+    return new TextDecoder(encoding, fatal, ignoreBOM);
 }
 
 
-TextDecoder::TextDecoder(const WTF::TextEncoding& encoding, bool fatal)
+TextDecoder::TextDecoder(const WTF::TextEncoding& encoding, bool fatal, bool ignoreBOM)
     : m_encoding(encoding)
     , m_codec(newTextCodec(encoding))
     , m_fatal(fatal)
+    , m_ignoreBOM(ignoreBOM)
     , m_bomSeen(false)
 {
 }
 
 TextDecoder::~TextDecoder()
 {
 }
 
 String TextDecoder::encoding() const
 {
@@ skipping 16 matching lines @@
     WTF::FlushBehavior flush = stream ? WTF::DoNotFlush : WTF::DataEOF;
 
     bool sawError = false;
     String s = m_codec->decode(start, length, flush, m_fatal, sawError);
 
     if (m_fatal && sawError) {
         exceptionState.throwDOMException(EncodingError, "The encoded data was not valid.");
         return String();
     }
 
-    if (!m_bomSeen && !s.isEmpty()) {
+    if (!m_ignoreBOM && !m_bomSeen && !s.isEmpty()) {
         m_bomSeen = true;
         String name(m_encoding.name());
         if ((name == "UTF-8" || name == "UTF-16LE" || name == "UTF-16BE") && s[0] == 0xFEFF)
             s.remove(0);
     }
 
     if (flush)
         m_bomSeen = false;
 
     return s;
 }
 
 } // namespace WebCore