normalize headers correctly

i18n flash message

app/assets/javascripts/compare.js

@@ -77,7 +77,7 @@ export default class Compare {
     }).then(({ data }) => {
       loading.hide();
       $target.html(data);
-      var className = '.' + $target[0].className.replace(' ', '.');
+      const className = '.' + $target[0].className.replace(' ', '.');
       localTimeAgo($('.js-timeago', className));
     });
   }

app/assets/javascripts/compare_autocomplete.js

 /* eslint-disable func-names, space-before-function-paren, one-var, no-var, one-var-declaration-per-line, object-shorthand, comma-dangle, prefer-arrow-callback, no-else-return, newline-per-chained-call, wrap-iife, max-len */
+import { __ } from './locale';
 import axios from './lib/utils/axios_utils';
 import flash from './flash';
 
@@ -19,7 +20,7 @@ export default function initCompareAutocomplete() {
           },
         }).then(({ data }) => {
           callback(data);
-        }).catch(() => flash('Error fetching refs'));
+        }).catch(() => flash(__('Error fetching refs')));
       },
       selectable: true,
       filterable: true,

app/assets/javascripts/groups/groups_filterable_list.js

 import FilterableList from '~/filterable_list';
 import eventHub from './event_hub';
-import { getParameterByName } from '../lib/utils/common_utils';
+import { normalizeHeaders, getParameterByName } from '../lib/utils/common_utils';
 
 export default class GroupFilterableList extends FilterableList {
   constructor({ form, filter, holder, filterEndpoint, pagePath, dropdownSel, filterInputField }) {
@@ -97,20 +97,11 @@ export default class GroupFilterableList extends FilterableList {
   onFilterSuccess(res, queryData) {
     const currentPath = this.getPagePath(queryData);
 
-    const paginationData = {
-      'X-Per-Page': res.headers['x-per-page'],
-      'X-Page': res.headers['x-page'],
-      'X-Total': res.headers['x-total'],
-      'X-Total-Pages': res.headers['x-total-pages'],
-      'X-Next-Page': res.headers['x-next-page'],
-      'X-Prev-Page': res.headers['x-prev-page'],
-    };
-
     window.history.replaceState({
       page: currentPath,
     }, document.title, currentPath);
 
     eventHub.$emit('updateGroups', res.data, Object.prototype.hasOwnProperty.call(queryData, this.filterInputField));
-    eventHub.$emit('updatePagination', paginationData);
+    eventHub.$emit('updatePagination', normalizeHeaders(res.headers));
   }
 }