Add ChromiumAATTest for testing AAT font support in the shaper

TBR=avi@chromium.org
BUG=354497
TEST=NONE

Review URL: https://codereview.chromium.org/206253006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@258429 0039d316-1c4b-4281-b951-d872f2087c98
3 files changed