[Merge of http://go/wvgerrit/16626] [Cherrypick from http://go/ag/858552 to nyc-dev branch] Setting umask to ensure only owner can access sensitive files. Fixes request_license_test which creates directories and files accessible by group and others. bug: 26567162 Change-Id: I63553ec9210f3a4c160cd4c4f2a49c9e0a4157db