This is a testharness.js-based test.
FAIL Interfaces and attributes of ServiceWorkerContainer assert_true: onmessageerror should be an attribute of ServiceWorkerContainer expected true got false
PASS Interfaces and attributes of ServiceWorker 
PASS Interfaces and attributes in ServiceWorkerGlobalScope 
FAIL ServiceWorkerGlobalScope assert_true: onmessageerror should be an attribute of ServiceWorkerGlobalScope expected true got false
PASS Clients 
PASS Client 
PASS WindowClient 
PASS CacheStorage 
PASS Cache 
PASS Event constructors 
Harness: the test ran to completion.