Merge branch '18714_bulk_assign_labels_icon' into 'master'

Fixes item icon state when for issues that have the same labels assigned

## What does this MR do?
Previously if all issues had the same labels the dropdown was showing the labels with indeterminate stated which is wrong. This MR fixes that and shows the correct state.

## What are the relevant issue numbers?
Fixes #18714

## Screenshots (if relevant)

**Before**

![label-before](/uploads/c65aa051e773dfea898a0d19767d6ade/label-before.gif)

**After**

![label](/uploads/73fd657d104d1081e189e0a9547d483b/label.gif)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- [ ] Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !4721

app/assets/javascripts/gl_dropdown.js.coffee

@@ -302,6 +302,9 @@ class GitLabDropdown
     if @options.setIndeterminateIds
       @options.setIndeterminateIds.call(@)
 
+    if @options.setActiveIds
+      @options.setActiveIds.call(@)
+
     # Makes indeterminate items effective
     if @fullData and @dropdown.find('.dropdown-menu-toggle').hasClass('js-filter-bulk-update')
       @parseData @fullData

app/assets/javascripts/labels_select.js.coffee

@@ -210,9 +210,21 @@ class @LabelsSelect
 
           if $dropdown.hasClass('js-filter-bulk-update')
             indeterminate = instance.indeterminateIds
+            active = instance.activeIds
+
             if indeterminate.indexOf(label.id) isnt -1
               selectedClass.push 'is-indeterminate'
 
+            if active.indexOf(label.id) isnt -1
+              # Remove is-indeterminate class if the item will be marked as active
+              i = selectedClass.indexOf 'is-indeterminate'
+              selectedClass.splice i, 1 unless i is -1
+
+              selectedClass.push 'is-active'
+
+              # Add input manually
+              instance.addInput @fieldName, label.id
+
           if $form.find("input[type='hidden']\
             [name='#{$dropdown.data('fieldName')}']\
             [value='#{this.id(label)}']").length
@@ -328,6 +340,10 @@ class @LabelsSelect
         setIndeterminateIds: ->
           if @dropdown.find('.dropdown-menu-toggle').hasClass('js-filter-bulk-update')
             @indeterminateIds = _this.getIndeterminateIds()
+
+        setActiveIds: ->
+          if @dropdown.find('.dropdown-menu-toggle').hasClass('js-filter-bulk-update')
+            @activeIds = _this.getActiveIds()
       )
 
     @bindEvents()
@@ -352,3 +368,12 @@ class @LabelsSelect
       label_ids.push $("#issue_#{issue_id}").data('labels')
 
     _.flatten(label_ids)
+
+  getActiveIds: ->
+    label_ids = []
+
+    $('.selected_issue:checked').each (i, el) ->
+      issue_id = $(el).data('id')
+      label_ids.push $("#issue_#{issue_id}").data('labels')
+
+    _.intersection.apply _, label_ids

spec/features/issues/bulk_assignment_labels_spec.rb

@@ -190,7 +190,8 @@ feature 'Issues > Labels bulk assignment', feature: true do
       end
       if unmark
         items.map do |item|
-          click_link item
+          # Make sure we are unmarking the item no matter the state it has currently
+          click_link item until find('a', text: item)[:class] == 'label-item'
         end
       end
     end