Fix performance issue for "Share project with other groups" page

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/javascripts/dispatcher.js.coffee

@@ -79,6 +79,8 @@ class Dispatcher
         new ProjectFork()
       when 'users:show'
         new User()
+      when 'projects:group_links:index'
+        new GroupsSelect()
 
     switch path.first()
       when 'admin'

app/controllers/projects/group_links_controller.rb

@@ -4,9 +4,6 @@ class Projects::GroupLinksController < Projects::ApplicationController
 
   def index
     @group_links = project.project_group_links.all
-    @available_groups = Group.all
-    @available_groups -= project.invited_groups
-    @available_groups -= [project.group]
   end
 
   def create

app/views/projects/group_links/index.html.haml

@@ -20,8 +20,8 @@
                 %i.icon-remove
                 disable sharing
 
-- if @available_groups.present?
-  .available-groups
+
+.available-groups
   %h4
     Can be shared with
   %div
@@ -29,7 +29,7 @@
       .form-group
         = label_tag :group_id, 'Group', class: 'control-label'
         .col-sm-10
-            = select_tag :group_id, options_from_collection_for_select(@available_groups, :id, :name), class: 'select2'
+          = groups_select_tag(:group_id)
       .form-group
         = label_tag :group_access, 'Max access level', class: 'control-label'
         .col-sm-10