refactor Network class

app/assets/javascripts/network/network.js

@@ -2,20 +2,18 @@
 
 import BranchGraph from './branch_graph';
 
-(function() {
-  this.Network = (function() {
-    function Network(opts) {
-      var vph;
-      $("#filter_ref").click(function() {
-        return $(this).closest('form').submit();
-      });
-      this.branch_graph = new BranchGraph($(".network-graph"), opts);
-      vph = $(window).height() - 250;
-      $('.network-graph').css({
-        'height': vph + 'px'
-      });
-    }
+export default (function() {
+  function Network(opts) {
+    var vph;
+    $("#filter_ref").click(function() {
+      return $(this).closest('form').submit();
+    });
+    this.branch_graph = new BranchGraph($(".network-graph"), opts);
+    vph = $(window).height() - 250;
+    $('.network-graph').css({
+      'height': vph + 'px'
+    });
+  }
 
-    return Network;
-  })();
-}).call(window);
+  return Network;
+})();

app/assets/javascripts/network/network_bundle.js

 /* eslint-disable func-names, space-before-function-paren, prefer-arrow-callback, quotes, no-var, vars-on-top, camelcase, comma-dangle, consistent-return, max-len */
-/* global Network */
 /* global ShortcutsNetwork */
 
-require('./network');
+import Network from './network';
 
 (function() {
   $(function() {