delete-ligature-001.html sometimes crashes on Windows Debug bot. See <http://build.webkit.org/results/Windows%20Debug%20(Tests)/r57783%20(12296)/results.html> and <http://build.webkit.org/results/Windows%20Debug%20(Tests)/r57779%20(12292)/results.html> for examples. This test doesn't seem to be crashing on the Windows Release bot. Maybe an assertion is failing?
<rdar://problem/7877404>
Haven't seen this in quite a while.