Avoid NPE in AnnotationsPropertySource if getAnnotations returns null

Closes gh-9914

spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/properties/AnnotationsPropertySource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -85,12 +85,15 @@ public class AnnotationsPropertySource extends EnumerablePropertySource<Class<?>
 
 	private List<Annotation> getMergedAnnotations(Class<?> root, Class<?> source) {
 		List<Annotation> mergedAnnotations = new ArrayList<Annotation>();
-		for (Annotation annotation : AnnotationUtils.getAnnotations(source)) {
+		Annotation[] annotations = AnnotationUtils.getAnnotations(source);
+		if (annotations != null) {
+			for (Annotation annotation : annotations) {
 				if (!AnnotationUtils.isInJavaLangAnnotationPackage(annotation)) {
 					mergedAnnotations
 							.add(findMergedAnnotation(root, annotation.annotationType()));
 				}
 			}
+		}
 		return mergedAnnotations;
 	}