Prevent chosen-drop elem from appearing when empty

Without checking to see if the total number of chosen results matches the total number of results in the `@results_data` array, when the `results_show` method is called, the chosen-drop elem will appear as an empty white box with a shadow - which to me, is an undesired effect.

The code changes are pretty straightforward.  I didn't see anywhere to write unit tests - although I'd be happy to write one for this if that is needed. 

Thanks for considering the changes!