Update baselines from the bots after r155477 (mac antialiased text changes).

Also delete the MacExpectations workaround file, which makes the
webkitpy tests pass again as well.

TBR=
BUG=264088

git-svn-id: svn://svn.chromium.org/blink/trunk@155478 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Clean up test expectations after r155477 (massive mac rebaselining).

TBR=
BUG=264088

Review URL: https://codereview.chromium.org/22077002

git-svn-id: svn://svn.chromium.org/blink/trunk@155479 bbb929c8-8fbe-4397-9dbb-9b2b20218538