Check for nil - fix intermittent test failure.

web/app/controllers/api_rsvp_requests_controller.rb

@@ -12,7 +12,8 @@ class ApiRsvpRequestsController < ApiController
       music_session = MusicSession.find(params[:session_id])
 
       # retrieve all requests for this session
-      if music_session.creator.id == current_user.id
+      creator = music_session.creator
+      if creator && creator.id == current_user.id
         @rsvp_requests = RsvpRequest.index(music_session, nil, params)
 
       # scope the response to the current user