Move MimeMultipartTransformer and HttpBodyHandler to mime and http_server packages.

pkg/http_server/lib/src/http_body_impl.dart

 // Copyright (c) 2013, 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;
+part of http_server;
 
 class _HttpBodyHandlerTransformer
     extends StreamEventTransformer<HttpRequest, HttpRequestBody> {
   final Encoding _defaultEncoding;
   _HttpBodyHandlerTransformer(this._defaultEncoding);
 
   void handleData(HttpRequest request, EventSink<HttpRequestBody> sink) {
     _HttpBodyHandler.processRequest(request, _defaultEncoding)
         .then(sink.add, onError: sink.addError);
   }
@@ skipping 127 matching lines @@
             break;
         }
         break;
 
       default:
         break;
     }
 
     return asBinary();
   }
+
+  // Utility function to synchronously decode a list of bytes.
+  static String _decodeString(List<int> bytes,
+                              [Encoding encoding = Encoding.UTF_8]) {
+    if (bytes.length == 0) return "";
+    var string;
+    var error;
+    var controller = new StreamController(sync: true);
+    controller.stream
+      .transform(new StringDecoder(encoding))
+      .listen((data) => string = data,
+              onError: (e) => error = e);
+    controller.add(bytes);
+    controller.close();
+    if (error != null) throw error;
+    assert(string != null);
+    return string;
+  }
 }
 
 class _HttpBodyFileUpload implements HttpBodyFileUpload {
   final ContentType contentType;
   final String filename;
   final dynamic content;
   _HttpBodyFileUpload(this.contentType, this.filename, this.content);
 }
 
 class _HttpBody implements HttpBody {
@@ skipping 27 matching lines @@
   _HttpClientResponseBody(HttpClientResponse response, HttpBody body)
       : super(body.contentType, body.type, body.body),
         this.response = response;
 
   int get statusCode => response.statusCode;
 
   String get reasonPhrase => response.reasonPhrase;
 
   HttpHeaders get headers => response.headers;
 }