/** @generated */
 @Override
 protected void removeChildVisual(final EditPart childEditPart) {
   if (removeFixedChild(childEditPart)) {
     return;
   }
   super.removeChildVisual(childEditPart);
 }
 /** @generated */
 @Override
 protected void addChildVisual(final EditPart childEditPart, final int index) {
   if (addFixedChild(childEditPart)) {
     return;
   }
   super.addChildVisual(childEditPart, -1);
 }
 /** @generated */
 @Override
 protected void createDefaultEditPolicies() {
   super.createDefaultEditPolicies();
   installEditPolicy(EditPolicyRoles.SEMANTIC_ROLE, new MessageAsyncItemSemanticEditPolicy());
   installEditPolicy(
       AppliedStereotypeLabelDisplayEditPolicy.STEREOTYPE_LABEL_POLICY,
       new AppliedStereotypeLinkLabelDisplayEditPolicy());
 }
 /** @generated */
 @Override
 protected void createDefaultEditPolicies() {
   super.createDefaultEditPolicies();
   installEditPolicy(EditPolicyRoles.SEMANTIC_ROLE, new TimeObservationEventSemanticEditPolicy());
 }