This is necessary so that Cygwin users have a python directory in depot_tools/,
which will soon be used by gyp_chromium.

BUG=335180

Review URL: https://codereview.chromium.org/141523009

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@245704 0039d316-1c4b-4281-b951-d872f2087c98