I didn't properly test the worker-related changes in the final version of r54972, and I screwed up unwrapping global objects when we're in a WorkerContext.
Created attachment 49092 [details]
Comment on attachment 49092 [details]
Is this covered by existing regression tests?
(In reply to comment #4)
> Is this covered by existing regression tests?
Yes, but unfortunately, most (all?) of the tests that cover v8-related worker code are run under a full build of chromium, so problems didn't show up in any buildbots until chromium tried to merge passed r54972.
I thought I had run those tests locally prior to committing r54972, but apparently I hadn't. Mea culpa.