Fixes an issue with the previous fix for the prevention of adding multiple filters
Are there points in the code the reviewer needs to double check?
Not really. See if it's the best solution
Why was this MR needed?
The previous MR https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/9406 introduced a fix to prevent multiple filters of the same type but it worked if you use only the keyboard. If the user uses the mouse to click on the filter input the options were incorrect.
