code: function ( loc, cbk, opts ) {
  
      if ( ! loc ) {
          return cbk( new Error( "Geocoder.geocode requires a location.") );
      }
  
      return this.providerObj.geocode(this.providerOpts, loc, cbk, opts);
  
    }
docs: Request geocoordinates of given `loc` from Google
  
  @param {String} loc, required
  @param {Function} cbk, required
  @param {Object} opts, optional
  @api public