Merge branch 'fix-cannot-move-project-error' into 'master'

Fix "Cannot move project" error message from popping up after a successful transfer

The JavaScript click handlers were never being removed, leading to duplicate requests when attempting to transfer a project to another namespace. The first transfer would succeed but the subsequent ones would fail, leading to the error message saying, "Cannot move project".

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/0c9f61294291514e0c2a48c204b6a1aa/image.png)

I attempted to write a unit test for this, but it was taking me too long to get it right.

Closes #1448 and #1128

See merge request !548

CHANGELOG

@@ -3,7 +3,7 @@ Please view this file on the master branch, on stable branches it's out of date.
 v 7.11.0 (unreleased)
   - Fix clone URL field and X11 Primary selection (Dmitry Medvinsky)
   - Ignore invalid lines in .gitmodules
-  -
+  - Fix "Cannot move project" error message from popping up after a successful transfer (Stan Hu)
   -
   -
   -

app/assets/javascripts/application.js.coffee

@@ -173,6 +173,7 @@ $ ->
     $(@).closest(".diff-file").find(".notes_holder").toggle()
     e.preventDefault()
 
+  $(document).off "click", '.js-confirm-danger'
   $(document).on "click", '.js-confirm-danger', (e) ->
     e.preventDefault()
     btn = $(e.target)

app/assets/javascripts/confirm_danger_modal.js.coffee

@@ -8,11 +8,13 @@ class @ConfirmDangerModal
     submit = $('.js-confirm-danger-submit')
     submit.disable()
 
+    $('.js-confirm-danger-input').off 'input'
     $('.js-confirm-danger-input').on 'input', ->
       if rstrip($(@).val()) is project_path
         submit.enable()
       else
         submit.disable()
 
+    $('.js-confirm-danger-submit').off 'click'
     $('.js-confirm-danger-submit').on 'click', =>
       @form.submit()