Created attachment 391929 [details]
This test is flaky crashing on Mac. It appears to have a regression point at r256910.
Crash log attached.
I have marked this test as crashing while this is investigated.
Seems more likely to be an ANGLE regression, r256784. Jason couldn't reproduce, but it's certainly happening on the bots.
Most likely when a page is retrieved from the back-forward cache it's not reinitializing all of the ANGLE-related data structures. Need to catch this in the debugger.
Removed flaky expectation in https://trac.webkit.org/changeset/260873/webkit since the test has been consistently passing for the past few weeks.