Add initial Random Access File information to Observatory

sdk/lib/io/file_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;
 
 // Read the file in blocks of size 64k.
 const int _BLOCK_SIZE = 64 * 1024;
 
 
@@ skipping 538 matching lines @@
   String toString() => "File: '$path'";
 
   static throwIfError(Object result, String msg, String path) {
     if (result is OSError) {
       throw new FileSystemException(msg, path, result);
     }
   }
 }
 
 
-class _RandomAccessFile implements RandomAccessFile {
+class _RandomAccessFile
+    extends Object with _ServiceObject
+    implements RandomAccessFile {
+  // Use default Map so we keep order.
+  static Map<int, _RandomAccessFile> _files = new Map<int, _RandomAccessFile>();
+
   final String path;
   int _id;
   bool _asyncDispatched = false;
   SendPort _fileService;
 
-  _RandomAccessFile(this._id, this.path);
+
+  _RandomAccessFile(this._id, this.path) {
+    _files[_serviceId] = this;
+  }
+
+  String get _serviceTypePath => 'io/file/randomaccessfiles';
+  String get _serviceTypeName => 'RandomAccessFile';
+
+  Map _toJSON(bool ref) {
+    var r = {
+      'id': _servicePath,
+      'type': _serviceType(ref),
+      'name': '$path',
+      'user_name': '$path',
+    };
+    if (ref) {
+      return r;
+    }
+    r['asyncDispatched'] = _asyncDispatched;
+    r['fd'] = _id;
+    return r;
+  }
+
+  void _maybePerformCleanup() {
+    if (closed) {
+      _files.remove(_serviceId);
+    }
+  }
 
   Future<RandomAccessFile> close() {
     return _dispatch(_FILE_CLOSE, [_id], markClosed: true).then((result) {
       if (result != -1) {
         _id = result;
+        _maybePerformCleanup();
         return this;
       } else {
         throw new FileSystemException("Cannot close file", path);
       }
     });
   }
 
   external static int _close(int id);
 
   void closeSync() {
     _checkAvailable();
     var id = _close(_id);
     if (id == -1) {
       throw new FileSystemException("Cannot close file", path);
     }
     _id = id;
+    _maybePerformCleanup();
   }
 
   Future<int> readByte() {
     return _dispatch(_FILE_READ_BYTE, [_id]).then((response) {
       if (_isErrorResponse(response)) {
         throw _exceptionFromResponse(response, "readByte failed", path);
       }
       return response;
     });
   }
@@ skipping 302 matching lines @@
   void _checkAvailable() {
     if (_asyncDispatched) {
       throw new FileSystemException("An async operation is currently pending",
                                     path);
     }
     if (closed) {
       throw new FileSystemException("File closed", path);
     }
   }
 }