Spotted on MultimediaViewer when running quibble with hhvm. The Qunit tests fail:
```
mmv.provider.Image
✖ Image load with preloading supported
HeadlessChrome 0.0.0 (Linux 0.0.0)
Promise rejected during "Image load with preloading supported": could not load image from /extensions/MultimediaViewer/resources/mmv/img/expand.svg
at mightThrow (http://localhost:9876/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=1ex5wzx:49:598)
at process (http://localhost:9876/load.php?debug=false&lang=en&modules=jquery%2Cmediawiki&only=scripts&skin=vector&version=1ex5wzx:50:269)
```
The HHVM server does not serve them apparently. It works fine with php7.
ZUUL_PROJECT=mediawiki/extensions/MultimediaViewer quibble --db sqlite --run qunit --skip-zuul --skip-deps
From Special:Version:
| Entry point | URL
|--|--
| Article path | /index.php/$1
| Script path | /
| index.php | /index.php
| api.php | /api.php
| load.php | /load.php