Add optional defaultEncoding to HttpBodyHandler, as a way to override default encoding for 'applica…

sdk/lib/io/http_utils.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
 class _HttpUtils {
-  static String decodeUrlEncodedString(String urlEncoded) {
+  static String decodeUrlEncodedString(
+      String urlEncoded,
+      {Encoding encoding: Encoding.UTF_8}) {
     // First check the string for any encoding.
     int index = 0;
     bool encoded = false;
     while (!encoded && index < urlEncoded.length) {
       encoded = urlEncoded[index] == "+" || urlEncoded[index] == "%";
       index++;
     }
     if (!encoded) return urlEncoded;
     index--;
 
@@ skipping 21 matching lines @@
               throw new ArgumentError("Invalid URL encoding");
             }
           }
         }
         bytes.add(byte);
         i += 2;
       } else {
         bytes.add(urlEncoded.codeUnitAt(i));
       }
     }
-    return decodeUtf8(bytes);
+    return _decodeString(bytes, encoding);
   }
 
-  static Map<String, String> splitQueryString(String queryString) {
+  static Map<String, String> splitQueryString(
+      String queryString,
+      {Encoding encoding: Encoding.UTF_8}) {
     Map<String, String> result = new Map<String, String>();
     int currentPosition = 0;
     while (currentPosition < queryString.length) {
       int position = queryString.indexOf("=", currentPosition);
       if (position == -1) {
         break;
       }
       String name = queryString.substring(currentPosition, position);
       currentPosition = position + 1;
       position = queryString.indexOf("&", currentPosition);
       String value;
       if (position == -1) {
         value = queryString.substring(currentPosition);
         currentPosition = queryString.length;
       } else {
         value = queryString.substring(currentPosition, position);
         currentPosition = position + 1;
       }
-      result[_HttpUtils.decodeUrlEncodedString(name)] =
-        _HttpUtils.decodeUrlEncodedString(value);
+      result[_HttpUtils.decodeUrlEncodedString(name, encoding: encoding)] =
+        _HttpUtils.decodeUrlEncodedString(value, encoding: encoding);
     }
     return result;
   }
 
   // From RFC 2616 section "3.3.1 Full Date"
   // HTTP-date    = rfc1123-date | rfc850-date | asctime-date
   // rfc1123-date = wkday "," SP date1 SP time SP "GMT"
   // rfc850-date  = weekday "," SP date2 SP time SP "GMT"
   // asctime-date = wkday SP date3 SP time SP 4DIGIT
   // date1        = 2DIGIT SP month SP 4DIGIT
@@ skipping 305 matching lines @@
     while ((amp = input.indexOf('&', offset)) >= 0) {
       buffer.write(input.substring(offset, amp));
       int end = input.indexOf(';', amp);
       parse(amp, end);
       offset = end + 1;
     }
     buffer.write(input.substring(offset));
     return buffer.toString();
   }
 }