JobSubmissionFiles don't set right permission after mkdirs

JobSubmissionFiles provide getStagingDir to get Staging Directory.If stagingArea missing, method will create new directory with this.

fs.mkdirs(stagingArea, new FsPermission(JOB_DIR_PERMISSION));

It seems create new directory with JOB_DIR_PERMISSION,but this permission will be apply by umask.If umask too strict , this permission may be 000(if umask is 700).So we should change permission after create.