wikihiero has the same problem as in T85007, though @Legoktm's comment on Patch Set 2 of <https://gerrit.wikimedia.org/r/#/c/183906/> seems to suggest that the ResourceLoaderRegisterModules hook should be used instead of $wgExtensionFunctions for conditional registration of modules.
```
There was 1 error:
1) ResourcesTest::testUnsatisfiableDependencies
Undefined index: ext.visualEditor.mwcore
/home/ki/Projects/mediawiki/core/tests/phpunit/structure/ResourcesTest.php:94
/home/ki/Projects/mediawiki/core/tests/phpunit/MediaWikiTestCase.php:141
--
There were 2 failures:
[...]
2) ResourcesTest::testMissingDependencies
The module 'ext.visualEditor.mwcore' required by 'ext.wikihiero.visualEditor' must exist
Failed asserting that an array contains 'ext.visualEditor.mwcore'.
/home/ki/Projects/mediawiki/core/tests/phpunit/structure/ResourcesTest.php:74
/home/ki/Projects/mediawiki/core/tests/phpunit/MediaWikiTestCase.php:141
```