[unrelated] Avoid AS2CS failure on bad ShadowExp parts

plugins/org.eclipse.ocl.xtext.essentialocl/src/org/eclipse/ocl/xtext/essentialocl/as2cs/EssentialOCLDeclarationVisitor.java

diff --git a/plugins/org.eclipse.ocl.xtext.essentialocl/src/org/eclipse/ocl/xtext/essentialocl/as2cs/EssentialOCLDeclarationVisitor.java b/plugins/org.eclipse.ocl.xtext.essentialocl/src/org/eclipse/ocl/xtext/essentialocl/as2cs/EssentialOCLDeclarationVisitor.java
index ca654df..5db9b09 100644
--- a/plugins/org.eclipse.ocl.xtext.essentialocl/src/org/eclipse/ocl/xtext/essentialocl/as2cs/EssentialOCLDeclarationVisitor.java
+++ b/plugins/org.eclipse.ocl.xtext.essentialocl/src/org/eclipse/ocl/xtext/essentialocl/as2cs/EssentialOCLDeclarationVisitor.java
@@ -660,6 +660,9 @@
 			csOwnedParts.add(context.visitDeclaration(ShadowPartCS.class, asPart));
 		}
 		csCurlyBracketedClause.setValue(asShadowExp.getValue());
+		if ((csOwnedParts.size() == 0) && (csCurlyBracketedClause.getValue() == null)) {
+			csCurlyBracketedClause.setValue("bad-value");
+		}
 		return csNameExp;
 	}