scripting: Null pointer dereference

Change-Id: I0d72ef34945065f68e9af8b0957dc440a74c14ce
Reviewed-on: https://gerrit.libreoffice.org/11923
Reviewed-by: Matthew Francis <mjay.francis@gmail.com>
Tested-by: Matthew Francis <mjay.francis@gmail.com>

scripting/java/com/sun/star/script/framework/provider/ScriptProvider.java

@@ -171,7 +171,7 @@ public abstract class ScriptProvider implements
                 } else {
                     // otherwise, check whether it's an XModel
                     m_xModel =
-                        UnoRuntime.queryInterface(XModel.class, m_xInvocContext.getScriptContainer());
+                        UnoRuntime.queryInterface(XModel.class, aArguments[0]);
                 }
 
                 if (m_xModel == null) {