**Steps to reproduce**
* View this change https://gerrit.wikimedia.org/r/#/c/311463/ (it passed when it was merged but doing a recheck fails)
* See the failed test https://integration.wikimedia.org/ci/job/mediawiki-extensions-qunit-jessie/19388/console
**Expected results**
* I expect the test to pass
**Actual results**
* It is failing with
16:56:04 18 12 2016 16:56:03.129:DEBUG [launcher]: Chrome (id 41038593) captured in 1.288 secs
16:56:04 18 12 2016 16:56:03.149:DEBUG [middleware:karma]: custom files null null
16:56:04 18 12 2016 16:56:03.149:DEBUG [middleware:karma]: Serving static request /context.html
16:56:04 18 12 2016 16:56:03.154:DEBUG [web-server]: serving: /home/jenkins/workspace/mediawiki-extensions-qunit-jessie/src/node_modules/karma/static/favicon.ico
16:56:04 18 12 2016 16:56:03.156:DEBUG [web-server]: serving: /home/jenkins/workspace/mediawiki-extensions-qunit-jessie/src/node_modules/karma/static/context.html
16:56:04 18 12 2016 16:56:03.169:DEBUG [middleware:source-files]: Requesting /base/node_modules/qunitjs/qunit/qunit.js?28e1c466df9848ed4d3a9fe432636b5a198b6c3e /
16:56:04 18 12 2016 16:56:03.169:DEBUG [middleware:source-files]: Fetching /home/jenkins/workspace/mediawiki-extensions-qunit-jessie/src/node_modules/qunitjs/qunit/qunit.js
16:56:04 18 12 2016 16:56:03.172:DEBUG [middleware:source-files]: Requesting /base/node_modules/karma-qunit/lib/adapter.js?2cc5e3594a3b8ae53e8218929324788866ad223b /
16:56:04 18 12 2016 16:56:03.173:DEBUG [middleware:source-files]: Fetching /home/jenkins/workspace/mediawiki-extensions-qunit-jessie/src/node_modules/karma-qunit/lib/adapter.js
16:56:04 18 12 2016 16:56:03.175:DEBUG [web-server]: serving (cached): /home/jenkins/workspace/mediawiki-extensions-qunit-jessie/src/node_modules/qunitjs/qunit/qunit.js
16:56:04 18 12 2016 16:56:03.178:DEBUG [web-server]: serving (cached): /home/jenkins/workspace/mediawiki-extensions-qunit-jessie/src/node_modules/karma-qunit/lib/adapter.js
16:56:04 18 12 2016 16:56:03.180:DEBUG [web-server]: serving: /home/jenkins/workspace/mediawiki-extensions-qunit-jessie/src/node_modules/karma/static/context.js
16:56:07 Chrome 55.0.2883 (Linux 0.0.0) ERROR
16:56:07 Script error.
16:56:07
16:56:07
16:56:07 18 12 2016 16:56:06.141:DEBUG [karma]: Run complete, exiting.
16:56:07 18 12 2016 16:56:06.142:DEBUG [launcher]: Disconnecting all browsers
16:56:07 18 12 2016 16:56:06.251:DEBUG [launcher]: Process Chrome exited with code 0
16:56:07 18 12 2016 16:56:06.251:DEBUG [temp-dir]: Cleaning temp dir /home/jenkins/tmpfs/jenkins-0/karma-41038593
16:56:07 18 12 2016 16:56:06.292:DEBUG [launcher]: Finished all browsers
16:56:07 Warning: Task "karma:main" failed. Use --force to continue.
Note: Strange the last merged patch https://gerrit.wikimedia.org/r/#/c/324959/ passed but doing recheck's on other patches are failing.