Fix comments in json.dart.

lib/json/json.dart

 // Copyright (c) 2011, 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.
 
 #library("json");
 
 // Pure Dart implementation of JSON protocol.
 
 /**
  * Utility class to parse JSON and serialize objects to JSON.
  */
 class JSON {
   /**
-   * Parses [:json:] and build the corresponding object.
+   * Parses [json] and build the corresponding object.
    */
   static parse(String json) {
     return _JsonParser.parse(json);
   }
 
   /**
-   * Checks validity of JSON source in [:str:] and returns its text
-   * length. Returns 0 if [:str:] does not begin with a valid JSON
+   * Checks validity of JSON source in [str] and returns its text
+   * length. Returns 0 if [str] does not begin with a valid JSON
    * object.
    */
   static int length(String str) {
     return _JsonParser.objectLength(str);
   }
 
   /**
-   * Serializes [:object:] into JSON string.
+   * Serializes [object] into JSON string.
    */
   static String stringify(Object object) {
     return JsonStringifier.stringify(object);
   }
 
   /**
-   * Serializes [:object:] into [:output:] stream.
+   * Serializes [object] into [output] stream.
    */
   static void printOn(Object object, StringBuffer output) {
     return JsonStringifier.printOn(object, output);
   }
 }
 
 //// Implementation ///////////////////////////////////////////////////////////
 
 // TODO(ajohnsen): Introduce when we have a common exception interface for json.
 class JSONParseException {
@@ skipping 498 matching lines @@
         first = false;
       });
       _sb.add('}');
       _seen.removeLast();
       return;
     } else {
       throw const JsonUnsupportedObjectType();
     }
   }
 }