This tests that invalid syntax triggers 'worker.onerror'.
On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
Page-level worker.onerror handler triggered:
PASS errorEvent.message is "Uncaught SyntaxError: Unexpected token '}'"
PASS stripURL(errorEvent.filename) is "[blob: URL]"
PASS errorEvent.lineno is 2
PASS errorEvent.colno is 9
PASS errorEvent.error is null
PASS successfullyParsed is true
TEST COMPLETE