Use createTempDir in getOrCreateLocalRootDirs...

to automatically remove the directory on shutdown.

Author: foxik

core/src/main/scala/org/apache/spark/util/Utils.scala

@@ -696,7 +696,7 @@ private[spark] object Utils extends Logging {
           try {
             val rootDir = new File(root)
             if (rootDir.exists || rootDir.mkdirs()) {
-              val dir = createDirectory(root)
+              val dir = createTempDir(root)
               chmod700(dir)
               Some(dir.getAbsolutePath)
             } else {