Evaluate type 1 charstrings for conversion to type 2.

Fixes #1936 and #2536

Locally on OSX the following changed:
TEST-UNEXPECTED-FAIL | eq fit11-talk | in firefoxaurora | rendering of page 8 != reference rendering
TEST-UNEXPECTED-FAIL | eq fit11-talk | in firefoxaurora | rendering of page 10 != reference rendering
TEST-UNEXPECTED-FAIL | eq fit11-talk | in firefoxaurora | rendering of page 11 != reference rendering