This patch is mostly about the arrow syntax.
Some places can not be updated because the arrow syntax also
changes the meaning of `this.…`, but some code relies on that.
Change-Id: Ida3ab0e0950a428fbd1a85f281013778ee879df4
In QUnit 2, QUnit.setup()/QUnit.teardown() were renamed, to be called
QUnit.beforeEach()/QUnit.afterEach(). Though we are insulated by this
through MediaWiki's wrapper for backwards compatibility, changing the
names of the functions we pass to the new names allows us to drop the
old ones.
Bug: T170872
Change-Id: I5bfca33c1d4d920d54c2c54b483be78c61b6d0d7
