Merge pull request #2353 from baskerville/random-image

Don't try to return an element from an empty set

frontend/ui/screensaver.lua

@@ -57,6 +57,9 @@ local function getRandomImage(dir)
             end
         end
     end
+    if i == 0 then
+        return nil
+    end
     return createWidgetFromFile(dir .. pics[math.random(i)])
 end