Minor Observatory UI tweaks.

runtime/observatory/lib/src/service/object.dart

 // Copyright (c) 2014, 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 service;
 
 /// Helper function for canceling a Future<StreamSubscription>.
 Future cancelFutureSubscription(
     Future<StreamSubscription> subscriptionFuture) async {
   if (subscriptionFuture != null) {
@@ skipping 1933 matching lines @@
     variables.sort(ServiceObject.LexicalSortName);
     functions.clear();
     functions.addAll(map['functions']);
     functions.sort(ServiceObject.LexicalSortName);
   }
 
   Future<ServiceObject> evaluate(String expression) {
     return isolate._eval(this, expression);
   }
 
+  Script get rootScript {
+    for (Script script in scripts) {
+      if (script.uri == uri) return script;
+    }
+    return null;
+  }
+
   String toString() => "Library($uri)";
 }
 
 class AllocationCount extends Observable {
   @observable int instances = 0;
   @observable int bytes = 0;
 
   void reset() {
     instances = 0;
     bytes = 0;
@@ skipping 1721 matching lines @@
     var v = list[i];
     if ((v is ObservableMap) && _isServiceMap(v)) {
       list[i] = owner.getFromMap(v);
     } else if (v is ObservableList) {
       _upgradeObservableList(v, owner);
     } else if (v is ObservableMap) {
       _upgradeObservableMap(v, owner);
     }
   }
 }