Disable the ACCELERATED_2D_CANVAS build flag on mac

BUG=81678
TEST=none

Review URL: http://codereview.chromium.org/7102003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@87482 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed