banchID typo in protected_branches_edit.js

While looking through some code, I noticed this typo:

https://gitlab.com/gitlab-org/gitlab-ce/blob/master/app/assets/javascripts/protected_branch_edit.js.es6#L43

$ git grep banch
app/assets/javascripts/protected_branch_edit.js.es6:          id: this.$wrap.data('banchId'),

How does this work?