Fix indexed_db strong mode warnings.

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

Index: tools/dom/templates/html/impl/impl_IDBFactory.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_IDBFactory.darttemplate b/tools/dom/templates/html/impl/impl_IDBFactory.darttemplate
index 6218e29cf597ef0913c2f09b35f52e632b7ce9fd..a14677894b5fcf127e7f2ce63616d897e103a138 100644
--- a/tools/dom/templates/html/impl/impl_IDBFactory.darttemplate
+++ b/tools/dom/templates/html/impl/impl_IDBFactory.darttemplate
@@ -49,14 +49,14 @@ $endif
 
   @DomName('IDBFactory.deleteDatabase')
   Future<IdbFactory> deleteDatabase(String name,
-      {void onBlocked(Event)}) {
+      {void onBlocked(Event e)}) {
     try {
       var request = _deleteDatabase(name);
 
       if (onBlocked != null) {
         request.onBlocked.listen(onBlocked);
       }
-      var completer = new Completer.sync();
+      var completer = new Completer<IdbFactory>.sync();
       request.onSuccess.listen((e) {
         completer.complete(this);
       });
@@ -100,12 +100,12 @@ $!MEMBERS
  * Ties a request to a completer, so the completer is completed when it succeeds
  * and errors out when the request errors.
  */
-Future _completeRequest(Request request) {
-  var completer = new Completer.sync();
+Future/*<T>*/ _completeRequest/*<T>*/(Request request) {
+  var completer = new Completer/*<T>*/.sync();
   // TODO: make sure that completer.complete is synchronous as transactions
   // may be committed if the result is not processed immediately.
   request.onSuccess.listen((e) {
-    completer.complete(request.result);
+    completer.complete(request.result as dynamic/*=T*/);
   });
   request.onError.listen(completer.completeError);
   return completer.future;