Increase atom feed test coverage. Prevent 500 error if description is missing

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

app/views/events/_event_issue.atom.haml

 %div{xmlns: "http://www.w3.org/1999/xhtml"}
-  = markdown issue.description
+  - if issue.description.present?
+    = markdown issue.description

app/views/events/_event_merge_request.atom.haml

 %div{xmlns: "http://www.w3.org/1999/xhtml"}
-  = markdown merge_request.description
+  - if merge_request.description.present?
+    = markdown merge_request.description

features/steps/dashboard/event_filters.rb

@@ -82,6 +82,4 @@ class EventFilters < Spinach::FeatureSteps
   When 'I click "merge" event filter' do
     click_link("merged_event_filter")
   end
-
 end
-

spec/features/atom/dashboard_spec.rb

@@ -10,5 +10,34 @@ describe "Dashboard Feed", feature: true  do
         page.body.should have_selector("feed title")
       end
     end
+
+    context 'feed content' do
+      let(:project) { create(:project) }
+      let(:issue) { create(:issue, project: project, author: user, description: '') }
+      let(:note) { create(:note, noteable: issue, author: user, note: 'Bug confirmed', project: project) }
+
+      before do
+        project.team << [user, :master]
+        issue_event(issue, user)
+        note_event(note, user)
+        visit dashboard_path(:atom, private_token: user.private_token)
+      end
+
+      it "should have issue opened event" do
+        page.body.should have_content("#{user.name} opened issue ##{issue.iid}")
+      end
+
+      it "should have issue comment event" do
+        page.body.should have_content("#{user.name} commented on issue ##{issue.iid}")
+      end
+    end
+  end
+
+  def issue_event(issue, user)
+    EventCreateService.new.open_issue(issue, user)
+  end
+
+  def note_event(note, user)
+    EventCreateService.new.leave_note(note, user)
   end
 end