This test sets the umask on a per-process basis and hence cannot be
used in multi-threaded runs.

R=yangguo@chromium.org
TEST=mjsunit/d8-os

Review URL: https://chromiumcodereview.appspot.com/9372018

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10655 ce2b1a6d-e550-0410-aec6-3dcde31c8c00