Try to recompile if there is no compile product

Author: gab1one

org.knime.scijava.scripting.node/src/org/knime/scijava/scripting/node/ui/SciJavaScriptingNodeDialog.java

@@ -266,8 +266,9 @@ private JPanel createDialogPanel(final boolean clean) {
 			m_component.remove(m_errorPanel);
 		}
 
-		// only recompile if needed
-		if (!m_settings.getScriptCode().equals(m_oldCode)) {
+		// only recompile if code changed or compileProduct null
+		if (!m_settings.getScriptCode().equals(m_oldCode)
+				|| m_compileProduct == null) {
 			m_oldCode = m_settings.getScriptCode();
 			try {
 				m_compileProduct = recompile(m_settings.getScriptCode(),