limit group boards filtered search milestones and labels to groups only

app/assets/javascripts/filtered_search/filtered_search_dropdown_manager.js

@@ -2,13 +2,14 @@ import DropLab from '~/droplab/drop_lab';
 import FilteredSearchContainer from './container';
 
 class FilteredSearchDropdownManager {
-  constructor(baseEndpoint = '', tokenizer, page) {
+  constructor(baseEndpoint = '', tokenizer, page, isGroup) {
     this.container = FilteredSearchContainer.container;
     this.baseEndpoint = baseEndpoint.replace(/\/$/, '');
     this.tokenizer = tokenizer;
     this.filteredSearchTokenKeys = gl.FilteredSearchTokenKeys;
     this.filteredSearchInput = this.container.querySelector('.filtered-search');
     this.page = page;
+    this.groupsOnly = page === 'boards' && isGroup;
 
     if (this.page === 'issues' || this.page === 'boards') {
       this.filteredSearchTokenKeys = gl.FilteredSearchTokenKeysIssuesEE;
@@ -47,7 +48,7 @@ class FilteredSearchDropdownManager {
         reference: null,
         gl: 'DropdownNonUser',
         extraArguments: {
-          endpoint: `${this.baseEndpoint}/milestones.json?only_group_milestones=true`,
+          endpoint: `${this.baseEndpoint}/milestones.json${this.groupsOnly ? '?only_group_milestones=true' : ''}`,
           symbol: '%',
         },
         element: this.container.querySelector('#js-dropdown-milestone'),
@@ -56,7 +57,7 @@ class FilteredSearchDropdownManager {
         reference: null,
         gl: 'DropdownNonUser',
         extraArguments: {
-          endpoint: `${this.baseEndpoint}/labels.json?only_group_labels=true`,
+          endpoint: `${this.baseEndpoint}/labels.json${this.groupsOnly ? '?only_group_labels=true' : ''}`,
           symbol: '~',
           preprocessing: gl.DropdownUtils.duplicateLabelPreprocessing,
         },

app/assets/javascripts/filtered_search/filtered_search_manager.js

@@ -63,7 +63,12 @@ class FilteredSearchManager {
 
     if (this.filteredSearchInput) {
       this.tokenizer = gl.FilteredSearchTokenizer;
-      this.dropdownManager = new gl.FilteredSearchDropdownManager(this.filteredSearchInput.getAttribute('data-base-endpoint') || '', this.tokenizer, this.page);
+      this.dropdownManager = new gl.FilteredSearchDropdownManager(
+        this.filteredSearchInput.getAttribute('data-base-endpoint') || '',
+        this.tokenizer,
+        this.page,
+        Boolean(this.filteredSearchInput.getAttribute('data-group-id')),
+      );
 
       this.recentSearchesRoot = new RecentSearchesRoot(
         this.recentSearchesStore,