fix the quiz submission preview inception issue in ember quizzes

fixes CNVS-13390

- test plan
  - enable draft state and quiz stats features
  - as a teacher
    - create a quiz with multiple attempts

  - as a student
    - take the quiz

  - as a teacher
    - go to speedgrader for this student's submission and add a note in the
      sidebar

  - as a student
    - go to your dashboard, the teacher's note should be in the sidebar
      under "Recent Feedback"
    - click on the note
    - it should bring you to the submission details page.
    - the ember version of the page should display in the frame
    - clicking on 'take the quiz again' should not cause inception

Change-Id: I1eb7d467ec08f8d3a1510602b4720483c1b1167c
Reviewed-on: https://gerrit.instructure.com/35871
Reviewed-by: Jason Madsen <jmadsen@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
QA-Review: Caleb Guanzon <cguanzon@instructure.com>
Product-Review: Derek DeVries <ddevries@instructure.com>

app/controllers/quizzes/quizzes_controller.rb

@@ -46,6 +46,10 @@ class Quizzes::QuizzesController < ApplicationController
           :quiz_statistics => true,
           :quiz_moderate   => @context.feature_enabled?(:quiz_moderate)
         })
+
+        # headless prevents inception in submission preview
+        setup_headless if params[:headless]
+
         render action: "fabulous_quizzes"
 
       else
@@ -99,7 +103,7 @@ class Quizzes::QuizzesController < ApplicationController
     if @context.feature_enabled?(:quiz_stats) &&
        @context.feature_enabled?(:draft_state) &&
        !params.key?(:take)
-      redirect_to ember_urls.course_quiz_url(@quiz.id)
+      redirect_to ember_urls.course_quiz_url(@quiz.id, headless: params[:headless])
       return
     end
 

app/stylesheets/ember_quizzes/show.scss

@@ -1,5 +1,6 @@
 #quiz-show {
   font-family: "Helvetica Neue", "Helvetica", "Arial", sans-serif;
+  background-color: #fff;
 
   .edit-header {
     padding-right: 20px;

app/views/quizzes/quizzes/fabulous_quizzes.html.erb

@@ -1,3 +1,6 @@
 <% jammit_css :quizzes_ember %>
 <% js_bundle :quizzes %>
 <% content_for :page_title, t(:page_titles, "Quizzes") %>
+<% content_for :head do %>
+  <base target="_top" />
+<% end %>

gems/canvas_ember_url/lib/canvas_ember_url.rb

@@ -9,8 +9,9 @@ module CanvasEmberUrl
       @mappings[:course_quizzes]
     end
 
-    def course_quiz_url(id)
-      "#{course_quizzes_url}#/#{id}"
+    def course_quiz_url(id, options={})
+      headless = '?headless=1' if options[:headless]
+      "#{course_quizzes_url}#{headless}#/#{id}"
     end
 
     def course_quiz_moderate_url(id)

gems/canvas_ember_url/spec/canvas_ember_url_spec.rb

@@ -36,6 +36,14 @@ describe CanvasEmberUrl::UrlMappings do
       it "should build the base url passed in" do
         mappings.course_quiz_url(1).should == "#{course_quizzes}#/1"
       end
+
+      it "should build the base url with headless param present" do
+        mappings.course_quiz_url(1, headless: 1).should == "#{course_quizzes}?headless=1#/1"
+      end
+
+      it "should build the base url with headless param empty" do
+        mappings.course_quiz_url(1, headless: nil).should == "#{course_quizzes}#/1"
+      end
     end
 
     describe "#course_quiz_moderate_url" do

spec/controllers/quizzes/quizzes_controller_spec.rb

@@ -375,6 +375,13 @@ describe Quizzes::QuizzesController do
       get 'show', :course_id => @course.id, :id => @quiz.id
       assert_redirected_to ember_urls.course_quiz_url(@quiz.id)
     end
+
+    it "should redirect to ember quiz stats app with headless if given" do
+      a = Account.default
+      a.feature_enabled?(:quiz_stats).should eql true
+      get 'show', :course_id => @course.id, :id => @quiz.id, :headless => 1
+      assert_redirected_to ember_urls.course_quiz_url(@quiz.id, headless: 1)
+    end
   end
 
   describe "GET 'managed_quiz_data'" do