fix(bpmn-replace): correctly replace sub process -> call activity

* when not morphing collapsed sub process with children
  into expanded sub process children must be removed

Related to camunda/camunda-modeler#739

lib/features/replace/BpmnReplace.js

@@ -151,6 +151,13 @@ function BpmnReplace(bpmnFactory, replace, selection, modeling, eventBus) {
       }
     }
 
+    // remove children if not expanding sub process
+    if (is(oldBusinessObject, 'bpmn:SubProcess')
+        && !isExpanded(oldBusinessObject)
+        && !is(newBusinessObject, 'bpmn:SubProcess')) {
+      hints.moveChildren = false;
+    }
+
     // transform collapsed/expanded pools
     if (is(oldBusinessObject, 'bpmn:Participant')) {
 

test/spec/features/replace/BpmnReplaceSpec.js

@@ -853,6 +853,25 @@ describe('features/replace - bpmn replace', function() {
       })
     );
 
+
+    it('should remove children of collapsed sub process not morphing into expanded',
+      inject(function(bpmnReplace, elementRegistry, modeling) {
+
+        // given
+        var element = elementRegistry.get('SubProcess_1');
+        var newElementData = {
+          type: 'bpmn:CallActivity'
+        };
+
+        modeling.toggleCollapse(element);
+
+        // when
+        var newElement = bpmnReplace.replaceElement(element, newElementData);
+
+        // then
+        expect(is(newElement, 'bpmn:CallActivity')).to.be.true;
+      }));
+
   });