Add initial Random Access File information to Observatory

runtime/bin/vmservice/client/lib/src/elements/io_view.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.
 
 library io_view_element;
 
 import 'dart:async';
 import 'observatory_element.dart';
 import 'service_ref.dart';
 import 'package:observatory/service.dart';
@@ skipping 52 matching lines @@
     _updateTimer = new Timer(new Duration(seconds: 1), _updateHttpServer);
   }
 
   void leftView() {
     super.leftView();
     if (_updateTimer != null) {
       _updateTimer.cancel();
       _updateTimer = null;
     }
   }
-}
+}
+
+@CustomTag('io-random-access-file-list-view')
+class IORandomAccessFileListViewElement extends ObservatoryElement {
+  @published ServiceMap list;
+
+  IORandomAccessFileListViewElement.created() : super.created();
+
+  void refresh(var done) {
+    list.reload().whenComplete(done);
+  }
+}
+
+@CustomTag('io-random-access-file-ref')
+class IORandomAccessFileRefElement extends ServiceRefElement {
+  IORandomAccessFileRefElement.created() : super.created();
+}
+
+@CustomTag('io-random-access-file-view')
+class IORandomAccessFileViewElement extends ObservatoryElement {
+  // TODO(ajohnsen): Create a RandomAccessFile object.
+  @published ServiceMap file;
+  Timer _updateTimer;
+
+  IORandomAccessFileViewElement.created() : super.created();
+
+  void refresh(var done) {
+    file.reload().whenComplete(done);
+  }
+
+  void _updateFile() {

[Anders Johnsen, 2014/05/25 17:59:23]

Can we create a RefreshingObservatoryElement class that we can use? I suspect
almost all IO views could be using it.

[Cutch, 2014/05/26 15:32:17]

Yes. We'll clean this up once we have some more elements.

+    refresh(() {
+      if (_updateTimer != null) {
+        _updateTimer = new Timer(new Duration(seconds: 1), _updateFile);
+      }
+    });
+  }
+
+  void enteredView() {
+    super.enteredView();
+    // Start a timer to update the isolate summary once a second.
+    _updateTimer = new Timer(new Duration(seconds: 1), _updateFile);
+  }
+
+  void leftView() {
+    super.leftView();
+    if (_updateTimer != null) {
+      _updateTimer.cancel();
+      _updateTimer = null;
+    }
+  }
+}