Enable standalone/io/http_test, splitting it into three separate tests.

runtime/bin/http.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.
 
 /**
  * HTTP status codes.
  */
 interface HttpStatus {
   static final int CONTINUE = 100;
   static final int SWITCHING_PROTOCOLS = 101;
@@ skipping 699 matching lines @@
   /**
    * Sets the handler that gets called if an error occurs while
    * connecting or processing the HTTP request.
    */
   void set onError(void callback(e));
 
   /**
    * Set this property to [:true:] if this connection should
    * automatically follow redirects. The default is [:true:].
    */
-  bool followRedirect;
+  bool followRedirects;
 
   /**
    * Set this property to the maximum number of redirects to follow
-   * when [followRedirect] is [:true:]. If this number is exceeded the
+   * when [followRedirects] is [:true:]. If this number is exceeded the
    * [onError] callback will be called with a [RedirectLimitExceeded]
    * exception. The default value is 5.
    */
   int maxRedirects;
 
   /**
    * Returns the series of redirects this connection has been through.
    */
   List<RedirectInfo> get redirects();
 
@@ skipping 33 matching lines @@
    * Returns the request headers.
    */
   HttpHeaders get headers();
 
   /**
    * Cookies to present to the server (in the Cookie header).
    */
   List<Cookie> get cookies();
 
   /**
+   * Gets and sets the requested persistent connection state.
+   * The default value is [:true:].
+   */
+  bool persistentConnection;
+
+  /**
    * Returns the output stream for the request. This is used to write
    * the request data. When all request data has been written close
    * the stream to indicate the end of the request.
    *
    * When this is accessed for the first time the request header is
    * send. Calling any methods that will change the header after
    * having retrieved the output stream will throw an exception.
    */
   OutputStream get outputStream();
 }
@@ skipping 13 matching lines @@
    */
   String get reasonPhrase();
 
   /**
    * Returns the content length of the request body. If the size of
    * the request body is not known in advance this -1.
    */
   int get contentLength();
 
   /**
+   * Gets the persistent connection state returned by the server.
+   */
+  bool get persistentConnection();
+
+  /**
    * Returns whether the status code is one of the normal redirect
    * codes [:HttpStatus.MOVED_PERMANENTLY:], [:HttpStatus.FOUND:],
    * [:HttpStatus.MOVED_TEMPORARILY:], [:HttpStatus.SEE_OTHER:] and
    * [:HttpStatus.TEMPORARY_REDIRECT:].
    */
   bool get isRedirect();
 
   /**
    * Returns the response headers.
    */
@@ skipping 63 matching lines @@
 class RedirectLimitExceededException extends RedirectException {
   const RedirectLimitExceededException(List<RedirectInfo> redirects)
       : super("Redirect limit exceeded", redirects);
 }
 
 
 class RedirectLoopException extends RedirectException {
   const RedirectLoopException(List<RedirectInfo> redirects)
       : super("Redirect loop detected", redirects);
 }