UrlResource applies StringUtils.getFilename against cleaned URL path

Issue: SPR-15411
(cherry picked from commit 702e01a)

Author: jhoeller

spring-core/src/main/java/org/springframework/core/io/UrlResource.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.
@@ -229,12 +229,11 @@ public Resource createRelative(String relativePath) throws MalformedURLException
 
 	/**
 	 * This implementation returns the name of the file that this URL refers to.
-	 * @see java.net.URL#getFile()
-	 * @see java.io.File#getName()
+	 * @see java.net.URL#getPath()
 	 */
 	@Override
 	public String getFilename() {
-		return new File(this.url.getFile()).getName();
+		return StringUtils.getFilename(this.cleanedUrl.getPath());
 	}
 
 	/**