Make any sort of ligatures, not just common ligatures, use the complex text path.

We can remove the incorrect hack in the layout test that used
common-ligatures, which forces the complex path.

BUG=22240

Review URL: https://codereview.chromium.org/193033003

git-svn-id: svn://svn.chromium.org/blink/trunk@168944 bbb929c8-8fbe-4397-9dbb-9b2b20218538