use shorter function syntax

controller/predicates/has_results_at_layers.js

@@ -8,7 +8,8 @@ const stackTraceLine = require('../../helper/stackTraceLine');
 // example usage: determining if the response contains only admin results
 
 module.exports = {
-  any: (layers) => (request, response) => {
+  any(layers) {
+    return (request, response) => {
       const has_results_at_any_layer = !_.isEmpty(
         _.intersection(
           // convert layers to an array if it isn't already one
@@ -22,9 +23,10 @@ module.exports = {
         stack_trace: stackTraceLine()
       }));
       return has_results_at_any_layer;
-
+    };
   },
-  all: (layers) => (request, response) => {
+  all(layers) {
+    return (request, response) => {
       const has_results_at_all_layers = _.isEmpty(
         _.difference(
           _.map(response.data, _.property('layer')),
@@ -38,6 +40,7 @@ module.exports = {
       }));
       return has_results_at_all_layers;
 
+    };
   }
 
 };