Re-enable multisampling for ATI cards on Mac 10.7.2 or newer. Also, the a few cards we enabled before, they are still not rendering correctly on older MacOSX, so remove them from exception list. BUG=83153 TEST= Review URL: http://codereview.chromium.org/8588041 git-svn-id: http://src.chromium.org/svn/trunk/deps/gpu/software_rendering_list@110790 4ff67af0-8c30-449e-8e8b-ad334ec8d88c