Clear nonAnnotatedClasses cache in afterSingletonsInstantiated

Issue: SPR-15175
(cherry picked from commit e566e25)

spring-context/src/main/java/org/springframework/scheduling/annotation/ScheduledAnnotationBeanPostProcessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -182,6 +182,9 @@ public class ScheduledAnnotationBeanPostProcessor
 
 	@Override
 	public void afterSingletonsInstantiated() {
+		// Remove resolved singleton classes from cache
+		this.nonAnnotatedClasses.clear();
+
 		if (this.applicationContext == null) {
 			// Not running in an ApplicationContext -> register tasks early...
 			finishRegistration();