MW has coding conventions for JavaScript (https://www.mediawiki.org/wiki/Manual:Coding_conventions/JavaScript)
During GSOC, I deliberately reviewed for some of these issues, but not all. Now, however, the code should be updated to fully comply.
In addition to the items listed there, it should pass jshint (a tool that checks code standards) and there should be a voting Jenkins job for this (so once it passes it stays that way).
Version: unspecified
Severity: normal