let gradebook1 be full-width, fixes: #9497

Change-Id: I74a6ec59cc47e036f6c72ca6871ad19e9767d740
Reviewed-on: https://gerrit.instructure.com/12290
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Bryan Madsen <bryan@instructure.com>

app/views/gradebooks/show.html.erb

@@ -1,4 +1,5 @@
 <% content_for :page_title do %><%= join_title t(:page_title, "Gradebook"), @context.name %><% end %>
+<% @body_classes << 'full-width' %>
 <% content_for :auto_discovery do %>
   <% if @context_enrollment %>
     <%= auto_discovery_link_tag(:atom, feeds_gradebook_url(@context_enrollment.feed_code), {:title => t('titles.feed', "Course Gradebook Atom Feed")}) %>

spec/views/gradebooks/show.html.erb_spec.rb

@@ -27,6 +27,7 @@ describe "/gradebooks/show" do
     assigns[:assignments] = [a]
     assigns[:students] = [@user]
     assigns[:submissions] = []
+    assigns[:body_classes] = []
     assigns[:gradebook_upload] = @course.build_gradebook_upload
     render "gradebooks/show"
     response.should_not be_nil