Refactor Future constructors.

tools/dom/templates/html/impl/impl_IDBObjectStore.darttemplate

 // Copyright (c) 2012, 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 $LIBRARYNAME;
 
 $(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
 
   @DomName('IDBObjectStore.add')
   Future add(value, [key]) {
     try {
       var request;
       if (key != null) {
         request = $dom_add(value, key);
       } else {
         request = $dom_add(value);
       }
       return _completeRequest(request);
     } catch (e, stacktrace) {
-      return new Future.immediateError(e, stacktrace);
+      return new Future.error(e, stacktrace);
     }
   }
 
   @DomName('IDBObjectStore.clear')
   Future clear() {
     try {
       return _completeRequest($dom_clear());
     } catch (e, stacktrace) {
-      return new Future.immediateError(e, stacktrace);
+      return new Future.error(e, stacktrace);
     }
   }
 
   @DomName('IDBObjectStore.delete')
   Future delete(key_OR_keyRange){
     try {
       return _completeRequest($dom_delete(key_OR_keyRange));
     } catch (e, stacktrace) {
-      return new Future.immediateError(e, stacktrace);
+      return new Future.error(e, stacktrace);
     }
   }
 
   @DomName('IDBObjectStore.count')
   Future<int> count([key_OR_range]) {
    try {
       var request;
       if (key_OR_range != null) {
         request = $dom_count(key_OR_range);
       } else {
         request = $dom_count();
       }
       return _completeRequest(request);
     } catch (e, stacktrace) {
-      return new Future.immediateError(e, stacktrace);
+      return new Future.error(e, stacktrace);
     }
   }
 
   @DomName('IDBObjectStore.put')
   Future put(value, [key]) {
     try {
       var request;
       if (key != null) {
         request = $dom_put(value, key);
       } else {
         request = $dom_put(value);
       }
       return _completeRequest(request);
     } catch (e, stacktrace) {
-      return new Future.immediateError(e, stacktrace);
+      return new Future.error(e, stacktrace);
     }
   }
 
   @DomName('IDBObjectStore.get')
   Future getObject(key) {
     try {
       var request = $dom_get(key);
 
       return _completeRequest(request);
     } catch (e, stacktrace) {
-      return new Future.immediateError(e, stacktrace);
+      return new Future.error(e, stacktrace);
     }
   }
 
   /**
    * Creates a stream of cursors over the records in this object store.
    *
    * **The stream must be manually advanced by calling [Cursor.next] after
    * each item or by specifying autoAdvance to be true.**
    *
    *     var cursors = objectStore.openCursor().listen(
@@ skipping 71 matching lines @@
       } else {
         controller.add(cursor);
         if (autoAdvance == true && controller.hasListener) {
           cursor.next();
         }
       }
     });
     return controller.stream;
   }
 }