QmlDesigner.NodeInstances: Use the node instance id member

Use the node instance id member instead of the model node id
Prevents a crash because the model node is allready invalid
and has no id anymore.

src/plugins/qmldesigner/designercore/instances/nodeinstanceview.cpp

@@ -699,9 +699,11 @@ void NodeInstanceView::removeIdFromContext(QObject *object)
 {
     if (hasInstanceForObject(object)) {
         NodeInstance instance = instanceForObject(object);
-        QString id = instance.modelNode().id();
-        if (!id.isEmpty())
-            engine()->rootContext()->setContextProperty(id, 0);
+        if (instance.internalInstance()) {
+            QString id = instance.internalInstance()->id();
+            if (!id.isEmpty())
+                engine()->rootContext()->setContextProperty(id, 0);
+        }
     }
 }
 

src/plugins/qmldesigner/designercore/instances/objectnodeinstance.cpp

@@ -199,6 +199,11 @@ void ObjectNodeInstance::setId(const QString &id)
     m_id = id;
 }
 
+QString ObjectNodeInstance::id() const
+{
+    return m_id;
+}
+
 bool ObjectNodeInstance::isQmlGraphicsItem() const
 {
     return false;

src/plugins/qmldesigner/designercore/instances/objectnodeinstance.h

@@ -106,6 +106,7 @@ public:
     virtual void reparent(const NodeInstance &oldParentInstance, const QString &oldParentProperty, const NodeInstance &newParentInstance, const QString &newParentProperty);
 
     void setId(const QString &id);
+    QString id() const;
 
     virtual bool isQmlGraphicsItem() const;
     virtual bool isGraphicsScene() const;