Extend with a language code in http accept languages

net/http/http_util.cc

 // Copyright (c) 2012 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.
 
 // The rules for parsing content-types were borrowed from Firefox:
 // http://lxr.mozilla.org/mozilla/source/netwerk/base/src/nsURLHelper.cpp#834
 
 #include "net/http/http_util.h"
 
 #include <algorithm>
@@ skipping 803 matching lines @@
   base::StringTokenizer tokenizer(str, std::string(1, '\0'));
   while (tokenizer.GetNext()) {
     disassembled_headers.append(tokenizer.token_begin(), tokenizer.token_end());
     disassembled_headers.append("\r\n");
   }
   disassembled_headers.append("\r\n");
 
   return disassembled_headers;
 }
 
-// TODO(jungshik): 1. If the list is 'fr-CA,fr-FR,en,de', we have to add
-// 'fr' after 'fr-CA' with the same q-value as 'fr-CA' because
-// web servers, in general, do not fall back to 'fr' and may end up picking
-// 'en' which has a lower preference than 'fr-CA' and 'fr-FR'.
-// 2. This function assumes that the input is a comma separated list
-// without any whitespace. As long as it comes from the preference and
-// a user does not manually edit the preference file, it's the case. Still,
-// we may have to make it more robust.
-std::string HttpUtil::GenerateAcceptLanguageHeader(
-    const std::string& raw_language_list) {
-  // We use integers for qvalue and qvalue decrement that are 10 times
-  // larger than actual values to avoid a problem with comparing
-  // two floating point numbers.
-  const unsigned int kQvalueDecrement10 = 2;
-  unsigned int qvalue10 = 10;
-  base::StringTokenizer t(raw_language_list, ",");
-  std::string lang_list_with_q;
-  while (t.GetNext()) {
-    std::string language = t.token();
-    if (qvalue10 == 10) {
-      // q=1.0 is implicit.
-      lang_list_with_q = language;
-    } else {
-      DCHECK_LT(qvalue10, 10U);
-      base::StringAppendF(&lang_list_with_q, ",%s;q=0.%d", language.c_str(),
-                          qvalue10);
-    }
-    // It does not make sense to have 'q=0'.
-    if (qvalue10 > kQvalueDecrement10)
-      qvalue10 -= kQvalueDecrement10;
-  }
-  return lang_list_with_q;
-}
-
 void HttpUtil::AppendHeaderIfMissing(const char* header_name,
                                      const std::string& header_value,
                                      std::string* headers) {
   if (header_value.empty())
     return;
   if (HttpUtil::HasHeader(*headers, header_name))
     return;
   *headers += std::string(header_name) + ": " + header_value + "\r\n";
 }
 
@@ skipping 279 matching lines @@
   return true;
 }
 
 bool HttpUtil::NameValuePairsIterator::IsQuote(char c) const {
   if (strict_quotes_)
     return c == '"';
   return HttpUtil::IsQuote(c);
 }
 
 }  // namespace net