Remove task abilities, since we will only ever show the user their own

app/controllers/dashboard/tasks_controller.rb

 class Dashboard::TasksController < Dashboard::ApplicationController
-  before_action :authorize_destroy_task!, only: [:destroy]
-
   def index
     @tasks = case params[:state]
       when 'done'
@@ -23,12 +21,6 @@ class Dashboard::TasksController < Dashboard::ApplicationController
 
   private
 
-  def authorize_destroy_task!
-    unless can?(current_user, :destroy_task, task)
-      return render_404
-    end
-  end
-
   def task
     @task ||= current_user.tasks.find(params[:id])
   end

app/models/ability.rb

@@ -17,7 +17,6 @@ class Ability
       when Namespace then namespace_abilities(user, subject)
       when GroupMember then group_member_abilities(user, subject)
       when ProjectMember then project_member_abilities(user, subject)
-      when Task then task_abilities(user, subject)
       else []
       end.concat(global_abilities(user))
     end
@@ -417,16 +416,6 @@ class Ability
       rules
     end
 
-    def task_abilities(user, task)
-      rules = []
-
-      if task && task.user == user
-        rules << :destroy_task
-      end
-
-      rules
-    end
-
     def abilities
       @abilities ||= begin
         abilities = Six.new