Revert "isLanguageSpecific should return false, if different domains are"

This reverts commit 55f69fbd20f686fe514db153e6015ee1b261d7f8.

plugins/org.yakindu.sct.model.stext/src/org/yakindu/sct/model/stext/validation/STextJavaValidator.java

@@ -811,17 +811,11 @@ public class STextJavaValidator extends AbstractSTextJavaValidator implements ST
 		if (!isResponsible)
 			return false;
 		Statechart statechart = getStatechart(eObject);
-		if(statechart == null)
-			return false;
 		if (domainID == null || !domainID.equals(statechart.getDomainID())) {
 			return false;
 		}
 		return true;
 	}
-	@Override
-	public boolean isLanguageSpecific() {
-		return false;
-	}
 
 	protected Statechart getStatechart(EObject context) {
 		final ContextElementAdapter provider = (ContextElementAdapter) EcoreUtil.getExistingAdapter(context.eResource(),