Roll grit to revision 139.

https://code.google.com/p/grit-i18n/source/detail?r=139:

- Improve platform support indications for policy documentation.

BUG=None

Review URL: https://codereview.chromium.org/91463002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237592 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237593 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237593