QmlDesigner: Ignore certain auxiliary data names when saving

Properties with the postfix '@internal' are not stored in the
QML file. Therefore they are not persistent.

Change-Id: I1f726c029f9db8c00bc85dc11c276c098e9a2a3a
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/qmldesigner/designercore/model/rewriterview.cpp

@@ -493,6 +493,9 @@ QString RewriterView::auxiliaryDataAsQML() const
                 if (key.endsWith("@NodeInstance"))
                     continue;
 
+                if (key.endsWith("@Internal"))
+                    continue;
+
                 const QVariant value = data.value(key.toUtf8());
                 QString strValue = value.toString();
                 if (static_cast<QMetaType::Type>(value.type()) == QMetaType::QString)