Fix radioController to be selected if it's model is active

Previously radioController options with "loadModel" set, i.e
those that switch between models, like
http://lab.dev.concord.org/interactives.html#interactives/sam/light-matter/sun-on-ground.json,
would not be selected when a new model was loaded.

If no property is set, nor any loadModel, we want to just do nothing when
a model reload events happens.

[#57182806]