Removed const from classes arrays in Observatory

runtime/observatory/lib/src/elements/field_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 field_view_element;
 
 import 'dart:async';
 import 'dart:html';
 import 'package:observatory/models.dart' as M;
 import 'package:observatory/src/elements/class_ref.dart';
@@ skipping 137 matching lines @@
       header += 'const ';
     }
     if (_field.declaredType.name == 'dynamic'){
       header += 'var';
     } else {
       header += _field.declaredType.name;
     }
     children = [
       new NavBarElement(queue: _r.queue)
         ..children = _createMenu(),
-      new DivElement()..classes = const ['content-centered-big']
+      new DivElement()..classes = ['content-centered-big']
         ..children = [
           new HeadingElement.h2()..text = '$header ${field.name}',
           new HRElement(),
           new ObjectCommonElement(_isolate, _field, _retainedSizes,
                                   _reachableSizes, _references, _retainingPaths,
                                   _instances, queue: _r.queue),
           new BRElement(),
           new DivElement()..classes = ['memberList']
             ..children = _createMembers(),
           new HRElement(),
@@ skipping 116 matching lines @@
   Future _refresh() async {
     _field = await _fields.get(_isolate, _field.id);
     if (_field.dartOwner is M.LibraryRef) {
       _library = _field.dartOwner;
     } else if (_field.dartOwner is M.ClassRef) {
       _library = (await _classes.get(_isolate, _field.dartOwner.id)).library;
     }
     _r.dirty();
   }
 }