test(util/model): able to clone 'inputOutput' property belonging to a subprocess

Closes camunda/camunda-modeler#513

test/fixtures/json/model/camunda.json

@@ -537,6 +537,8 @@
           "bpmn:GlobalBusinessRuleTask",
           "bpmn:GlobalTask",
           "bpmn:GlobalManualTask",
+          "bpmn:SubProcess",
+          "bpmn:Transaction",
           "bpmn:IntermediateCatchEvent",
           "bpmn:IntermediateThrowEvent",
           "bpmn:EndEvent",

test/spec/util/ModelCloneHelperSpec.js

@@ -159,6 +159,12 @@ describe('util/ModelCloneHelper', function() {
         extensionElements: extensionElements
       });
 
+      var subProcess = helper.clone(userTask, moddle.create('bpmn:SubProcess'), [
+        'bpmn:extensionElements'
+      ]);
+
+      expect(subProcess.extensionElements.values[0].$type).to.equal('camunda:InputOutput');
+
       var serviceTask = helper.clone(userTask, moddle.create('bpmn:ServiceTask'), [
         'bpmn:extensionElements',
         'camunda:inputOutput'