QmlDesigner: Disable validator for connection source

Change-Id: If51f2336364b9e2a44ad7f4657b9b6245a66143b
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/qmldesigner/qmldesignerextension/connectioneditor/delegates.cpp

@@ -313,6 +313,7 @@ QWidget *ConnectionDelegate::createEditor(QWidget *parent, const QStyleOptionVie
             QString itemText = tr("Change to default state");
             QString source = QString::fromLatin1("{ %1.state = \"\" }").arg(rootModelNode.id());
             connectionComboBox->addItem(itemText, source);
+            connectionComboBox->disableValidator();
 
             foreach (const QmlModelState &state, QmlItemNode(rootModelNode).states().allStates()) {
                 QString itemText = tr("Change state to %1").arg(state.name());