title: How to get a layer from a feature in Openlayers 3?
body: <p>I can't find a way to go from a feature in a selection event to a layer that it may be a part of without traversing all the features of all my map layers, or storing an artificial layer ID within every feature at creation. Is this just not possible yet? </p>
  
  <p>ol.js 3.7.0
    ol.interaction.Selection -> click -> callback( event ){ event.selected[0] }</p>
  
  <p>In another part of my app, I would like to go from the feature to the layer to determine the style being used on the feature, specifically whether or not it's visible.</p>
  
  <p>ol.Feature.getStyle() || ol.Feature -> (layer?) -> getStyle()</p>