Allow GTMMethodCheck to compile under ARC, avoiding the need for
-fno-objc-arc everywhere it might be used.

DELTA=9  (8 added, 0 deleted, 1 changed)

git-svn-id: http://google-toolbox-for-mac.googlecode.com/svn/trunk@599 7dc7ac4e-7543-0410-b95c-c1676fc8e2a3