Template/instance widget: Pass display path info down to content ...

.. to allow resolution of relative path names

Fixes #2127

app/display/representation-javafx/src/main/java/org/csstudio/display/builder/representation/javafx/widgets/TemplateInstanceRepresentation.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2021 Oak Ridge National Laboratory.
+ * Copyright (c) 2021-2022 Oak Ridge National Laboratory.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -333,6 +333,11 @@ private void instantiateTemplateAndRepresent()
             // in timeouts of the editor awaiting complete representation
             new_model.setUserData(DisplayModel.USER_DATA_EMBEDDING_WIDGET, model_widget);
 
+            // Pass display file info down to embedded model for resource lookup
+            final DisplayModel parent_model = model_widget.getDisplayModel();
+            final String input_file = parent_model.getUserData(DisplayModel.USER_DATA_INPUT_FILE);
+            new_model.setUserData(DisplayModel.USER_DATA_INPUT_FILE, input_file);
+
             if (template.getChildren().size() > 0)
             {
                 final int w = template.propWidth().getValue();