MvcResult returns asyncResult after asyncDispatch

Issue: SPR-16648

spring-test/src/test/java/org/springframework/test/web/servlet/DefaultMvcResultTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2018 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,6 +15,8 @@
  */
 package org.springframework.test.web.servlet;
 
+import java.util.concurrent.CountDownLatch;
+
 import org.junit.Before;
 import org.junit.Test;
 
@@ -40,6 +42,7 @@ public class DefaultMvcResultTests {
 	@Test
 	public void getAsyncResultSuccess() throws Exception {
 		this.mvcResult.setAsyncResult("Foo");
+		this.mvcResult.setAsyncDispatchLatch(new CountDownLatch(0));
 		assertEquals("Foo", this.mvcResult.getAsyncResult());
 	}