expr.util: also delete the headers itself in the delete handlers

Author: Alexander Pann

code/languages/org.iets3.opensource/languages/org.iets3.core.expr.util/models/editor.mps

@@ -877,6 +877,14 @@
                         </node>
                       </node>
                     </node>
+                    <node concept="3clFbF" id="25cxNQTSsKR" role="3cqZAp">
+                      <node concept="2OqwBi" id="25cxNQTSt4M" role="3clFbG">
+                        <node concept="37vLTw" id="25cxNQTSsKP" role="2Oq$k0">
+                          <ref role="3cqZAo" node="3DYDRw0KdUw" resolve="h" />
+                        </node>
+                        <node concept="3YRAZt" id="25cxNQTStrg" role="2OqNvi" />
+                      </node>
+                    </node>
                   </node>
                 </node>
                 <node concept="1g0IQG" id="6VI$CVnK8Qj" role="1geGt4">
@@ -1007,6 +1015,14 @@
                           </node>
                         </node>
                       </node>
+                      <node concept="3clFbF" id="25cxNQTQS25" role="3cqZAp">
+                        <node concept="2OqwBi" id="25cxNQTQSlo" role="3clFbG">
+                          <node concept="37vLTw" id="25cxNQTQS23" role="2Oq$k0">
+                            <ref role="3cqZAo" node="3DYDRw0Kg7o" resolve="h" />
+                          </node>
+                          <node concept="3YRAZt" id="25cxNQTQSG4" role="2OqNvi" />
+                        </node>
+                      </node>
                     </node>
                   </node>
                   <node concept="1g0IQG" id="6VI$CVnLerj" role="1geGt4">