Mac: Scaffolding for sandboxing GPU process.

The sandbox config allows everything for now; I will put in restrictions in a follow-up CL (which should be small).

This CL should have no visible effect (other than changing a few LOG(WARNING) to LOG(ERROR)).

BUG=48607
TEST=GPU process still works

Review URL: http://codereview.chromium.org/5491001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@67939 0039d316-1c4b-4281-b951-d872f2087c98
14 files changed