Improve and fix specs for raw trace

spec/features/builds_spec.rb

@@ -96,7 +96,7 @@ describe "Builds" do
 
       it do
         page.within('.build-controls') do
-          expect(page).to have_content 'Raw'
+          expect(page).to have_link 'Raw'
         end
       end
     end
@@ -137,13 +137,17 @@ describe "Builds" do
 
   describe "GET /:project/builds/:id/raw" do
     before do
+      Capybara.current_session.driver.header('X-Sendfile-Type', 'X-Sendfile')
       @build.run!
       @build.trace = 'BUILD TRACE'
       visit namespace_project_build_path(@project.namespace, @project, @build)
-      page.within('.build-controls') { click_link 'Raw' }
     end
 
-    it { expect(page.response_headers['Content-Type']).to eq('text/plain; charset=utf-8') }
-    it { expect(page.response_headers['X-Sendfile']).to eq(@build.path_to_trace) }
+    it 'sends the right headers' do
+      page.within('.build-controls') { click_link 'Raw' }
+
+      expect(page.response_headers['Content-Type']).to eq('text/plain; charset=utf-8')
+      expect(page.response_headers['X-Sendfile']).to eq(@build.path_to_trace)
+    end
   end
 end