GL dropdown default toggle color

app/assets/javascripts/gl_dropdown.js.coffee

@@ -617,7 +617,14 @@ class GitLabDropdown
       $dropdownContent.scrollTop(listItemTop - dropdownContentTop)
 
   updateLabel: (selected = null, el = null, instance = null, added = false) =>
-    $(@el).find(".dropdown-toggle-text").text @options.toggleLabel(selected, el, instance, added)
+    $toggleText = $(@el).find(".dropdown-toggle-text")
+    $toggleText.text @options.toggleLabel(selected, el, instance, added)
+
+    if @options.defaultLabel
+      if $toggleText.text().trim() is @options.defaultLabel
+        $toggleText.addClass('is-default')
+      else
+        $toggleText.removeClass('is-default')
 
 $.fn.glDropdown = (opts) ->
   return @.each ->

app/assets/javascripts/labels_select.js.coffee

@@ -4,6 +4,7 @@ class @LabelsSelect
 
     $('.js-label-select').each (i, dropdown) ->
       $dropdown = $(dropdown)
+      $toggleText = $dropdown.find('.dropdown-toggle-text')
       projectId = $dropdown.data('project-id')
       labelUrl = $dropdown.data('labels')
       issueUpdateURL = $dropdown.data('issueUpdate')
@@ -280,12 +281,16 @@ class @LabelsSelect
             index = selectedLabels.indexOf selected.title
             selectedLabels.splice index, 1
 
+          if selected.id? and selected.id is 0
+            selectedLabels = []
+
           if selectedLabels.length > 1
             "#{selectedLabels[0]} +#{selectedLabels.length - 1} more"
           else if selectedLabels.length is 1
             selectedLabels[0]
           else
             defaultLabel
+        defaultLabel: defaultLabel
         fieldName: $dropdown.data('field-name')
         id: (label) ->
           if $dropdown.hasClass('js-issuable-form-dropdown')

app/assets/javascripts/milestone_select.js.coffee

@@ -70,11 +70,12 @@ class @MilestoneSelect
         search:
           fields: ['title']
         selectable: true
-        toggleLabel: (selected) ->
-          if selected && 'id' of selected
+        toggleLabel: (selected, el, e, added) ->
+          if selected and 'id' of selected and added
             selected.title
           else
             defaultLabel
+        defaultLabel: defaultLabel
         fieldName: $dropdown.data('field-name')
         text: (milestone) ->
           _.escape(milestone.title)

app/assets/javascripts/users_select.js.coffee

@@ -142,12 +142,12 @@ class @UsersSelect
         selectable: true
         fieldName: $dropdown.data('field-name')
 
-        toggleLabel: (selected) ->
-          if selected && 'id' of selected
+        toggleLabel: (selected, el, e, added) ->
+          if selected and 'id' of selected and added
             if selected.text then selected.text else selected.name
           else
             defaultLabel
-
+        defaultLabel: defaultLabel
         inputId: 'issue_assignee_id'
 
         hidden: (e) ->

app/assets/stylesheets/framework/dropdowns.scss

@@ -562,3 +562,9 @@
   display: block;
   color: $gl-placeholder-color;
 }
+
+.dropdown-toggle-text {
+  &.is-default {
+    color: $gl-placeholder-color;
+  }
+}

app/helpers/dropdowns_helper.rb

@@ -40,8 +40,9 @@ module DropdownsHelper
   end
 
   def dropdown_toggle(toggle_text, data_attr, options = {})
+    default_label = options[:data][:default_label]
     content_tag(:button, class: "dropdown-menu-toggle #{options[:toggle_class] if options.has_key?(:toggle_class)}", id: (options[:id] if options.has_key?(:id)), type: "button", data: data_attr) do
-      output = content_tag(:span, toggle_text, class: "dropdown-toggle-text")
+      output = content_tag(:span, toggle_text, class: "dropdown-toggle-text #{'is-default' if toggle_text == default_label}")
       output << icon('chevron-down')
       output.html_safe
     end

app/views/shared/issuable/_label_dropdown.html.haml

@@ -18,7 +18,7 @@
       = hidden_field_tag data_options[:field_name], label, id: nil
 .dropdown
   %button.dropdown-menu-toggle.js-label-select.js-multiselect{class: classes.join(' '), type: "button", data: dropdown_data}
-    %span.dropdown-toggle-text
+    %span.dropdown-toggle-text{ class: ("is-default" if selected_toggle) }
       = h(multi_label_name(selected_toggle || selected, "Label"))
     = icon('chevron-down')
   .dropdown-menu.dropdown-select.dropdown-menu-paging.dropdown-menu-labels.dropdown-menu-selectable

app/views/shared/issuable/_milestone_dropdown.html.haml

 - project = @target_project || @project
-- selected_text = project.milestones.find(selected).try(:name)
+- selected_text = project.milestones.find_by_id(selected).try(:name)
 - if selected.present?
   = hidden_field_tag(name, selected)
 = dropdown_tag(milestone_dropdown_label(selected_text), options: { title: "Filter by milestone", toggle_class: "js-milestone-select js-filter-submit #{extra_class}", filter: true, dropdown_class: "dropdown-menu-selectable",