Refactor(createFlash): use non-deprecated function

Migrate away from `deprecatedCreateFlash` and use
`createFlash` instead.

Manual changes

Epic:
https://gitlab.com/groups/gitlab-org/-/epics/3895

app/assets/javascripts/create_merge_request_dropdown.js

-/* eslint-disable no-new */
 import { debounce } from 'lodash';
 import {
   init as initConfidentialMergeRequest,
@@ -8,7 +7,7 @@ import {
 import confidentialMergeRequestState from './confidential_merge_request/state';
 import DropLab from './droplab/drop_lab';
 import ISetter from './droplab/plugins/input_setter';
-import { deprecatedCreateFlash as Flash } from './flash';
+import createFlash from './flash';
 import axios from './lib/utils/axios_utils';
 import { __, sprintf } from './locale';
 
@@ -132,7 +131,9 @@ export default class CreateMergeRequestDropdown {
       .catch(() => {
         this.unavailable();
         this.disable();
-        Flash(__('Failed to check related branches.'));
+        createFlash({
+          message: __('Failed to check related branches.'),
+        });
       });
   }
 
@@ -147,7 +148,11 @@ export default class CreateMergeRequestDropdown {
         this.branchCreated = true;
         window.location.href = data.url;
       })
-      .catch(() => Flash(__('Failed to create a branch for this issue. Please try again.')));
+      .catch(() =>
+        createFlash({
+          message: __('Failed to create a branch for this issue. Please try again.'),
+        }),
+      );
   }
 
   createMergeRequest() {
@@ -163,7 +168,11 @@ export default class CreateMergeRequestDropdown {
         this.mergeRequestCreated = true;
         window.location.href = data.url;
       })
-      .catch(() => Flash(__('Failed to create Merge Request. Please try again.')));
+      .catch(() =>
+        createFlash({
+          message: __('Failed to create Merge Request. Please try again.'),
+        }),
+      );
   }
 
   disable() {
@@ -256,7 +265,9 @@ export default class CreateMergeRequestDropdown {
       .catch(() => {
         this.unavailable();
         this.disable();
-        new Flash(__('Failed to get ref.'));
+        createFlash({
+          message: __('Failed to get ref.'),
+        });
 
         this.isGettingRef = false;
 

app/assets/javascripts/filtered_search/dropdown_emoji.js

 import { __ } from '~/locale';
 import Ajax from '../droplab/plugins/ajax';
 import Filter from '../droplab/plugins/filter';
-import { deprecatedCreateFlash as Flash } from '../flash';
+import createFlash from '../flash';
 import DropdownUtils from './dropdown_utils';
 import FilteredSearchDropdown from './filtered_search_dropdown';
 
@@ -14,9 +14,9 @@ export default class DropdownEmoji extends FilteredSearchDropdown {
         method: 'setData',
         loadingTemplate: this.loadingTemplate,
         onError() {
-          /* eslint-disable no-new */
-          new Flash(__('An error occurred fetching the dropdown data.'));
-          /* eslint-enable no-new */
+          createFlash({
+            message: __('An error occurred fetching the dropdown data.'),
+          });
         },
       },
       Filter: {

app/assets/javascripts/filtered_search/dropdown_non_user.js

 import { __ } from '~/locale';
 import Ajax from '../droplab/plugins/ajax';
 import Filter from '../droplab/plugins/filter';
-import { deprecatedCreateFlash as Flash } from '../flash';
+import createFlash from '../flash';
 import DropdownUtils from './dropdown_utils';
 import FilteredSearchDropdown from './filtered_search_dropdown';
 
@@ -17,9 +17,9 @@ export default class DropdownNonUser extends FilteredSearchDropdown {
         loadingTemplate: this.loadingTemplate,
         preprocessing,
         onError() {
-          /* eslint-disable no-new */
-          new Flash(__('An error occurred fetching the dropdown data.'));
-          /* eslint-enable no-new */
+          createFlash({
+            message: __('An error occurred fetching the dropdown data.'),
+          });
         },
       },
       Filter: {

app/assets/javascripts/filtered_search/filtered_search_manager.js

@@ -10,7 +10,7 @@ import {
   DOWN_KEY_CODE,
 } from '~/lib/utils/keycodes';
 import { __ } from '~/locale';
-import { deprecatedCreateFlash as Flash } from '../flash';
+import createFlash from '../flash';
 import { addClassIfElementExists } from '../lib/utils/dom_utils';
 import { visitUrl } from '../lib/utils/url_utility';
 import FilteredSearchContainer from './container';
@@ -92,8 +92,9 @@ export default class FilteredSearchManager {
       .fetch()
       .catch((error) => {
         if (error.name === 'RecentSearchesServiceError') return undefined;
-        // eslint-disable-next-line no-new
-        new Flash(__('An error occurred while parsing recent searches'));
+        createFlash({
+          message: __('An error occurred while parsing recent searches'),
+        });
         // Gracefully fail to empty array
         return [];
       })

app/assets/javascripts/notes.js

@@ -22,7 +22,7 @@ import syntaxHighlight from '~/syntax_highlight';
 import Autosave from './autosave';
 import loadAwardsHandler from './awards_handler';
 import CommentTypeToggle from './comment_type_toggle';
-import { deprecatedCreateFlash as Flash } from './flash';
+import createFlash from './flash';
 import { defaultAutocompleteConfig } from './gfm_auto_complete';
 import GLForm from './gl_form';
 import axios from './lib/utils/axios_utils';
@@ -399,7 +399,11 @@ export default class Notes {
         if (noteEntity.commands_changes && Object.keys(noteEntity.commands_changes).length > 0) {
           $notesList.find('.system-note.being-posted').remove();
         }
-        this.addFlash(noteEntity.errors.commands_only, 'notice', this.parentTimeline.get(0));
+        this.addFlash({
+          message: noteEntity.errors.commands_only,
+          type: 'notice',
+          parent: this.parentTimeline.get(0),
+        });
         this.refresh();
       }
       return;
@@ -620,20 +624,21 @@ export default class Notes {
     } else if ($form.hasClass('js-discussion-note-form')) {
       formParentTimeline = $form.closest('.discussion-notes').find('.notes');
     }
-    return this.addFlash(
-      __(
+    return this.addFlash({
+      message: __(
         'Your comment could not be submitted! Please check your network connection and try again.',
       ),
-      'alert',
-      formParentTimeline.get(0),
-    );
+      type: 'alert',
+      parent: formParentTimeline.get(0),
+    });
   }
 
   updateNoteError() {
-    // eslint-disable-next-line no-new
-    new Flash(
-      __('Your comment could not be updated! Please check your network connection and try again.'),
-    );
+    createFlash({
+      message: __(
+        'Your comment could not be updated! Please check your network connection and try again.',
+      ),
+    });
   }
 
   /**
@@ -1289,7 +1294,7 @@ export default class Notes {
   }
 
   addFlash(...flashParams) {
-    this.flashContainer = new Flash(...flashParams);
+    this.flashContainer = createFlash(...flashParams);
   }
 
   clearFlash() {

app/assets/javascripts/vue_merge_request_widget/components/states/ready_to_merge.vue

@@ -15,10 +15,10 @@ import { isEmpty } from 'lodash';
 import readyToMergeMixin from 'ee_else_ce/vue_merge_request_widget/mixins/ready_to_merge';
 import readyToMergeQuery from 'ee_else_ce/vue_merge_request_widget/queries/states/ready_to_merge.query.graphql';
 import { refreshUserMergeRequestCounts } from '~/commons/nav/user_merge_requests';
+import createFlash from '~/flash';
 import simplePoll from '~/lib/utils/simple_poll';
 import { __ } from '~/locale';
 import glFeatureFlagMixin from '~/vue_shared/mixins/gl_feature_flags_mixin';
-import { deprecatedCreateFlash as Flash } from '../../../flash';
 import MergeRequest from '../../../merge_request';
 import { AUTO_MERGE_STRATEGIES, DANGER, INFO, WARNING } from '../../constants';
 import eventHub from '../../event_hub';
@@ -351,7 +351,9 @@ export default {
         })
         .catch(() => {
           this.isMakingRequest = false;
-          new Flash(__('Something went wrong. Please try again.')); // eslint-disable-line
+          createFlash({
+            message: __('Something went wrong. Please try again.'),
+          });
         });
     },
     handleMergeImmediatelyButtonClick() {
@@ -402,7 +404,9 @@ export default {
           }
         })
         .catch(() => {
-          new Flash(__('Something went wrong while merging this merge request. Please try again.')); // eslint-disable-line
+          createFlash({
+            message: __('Something went wrong while merging this merge request. Please try again.'),
+          });
           stopPolling();
         });
     },
@@ -432,7 +436,9 @@ export default {
           }
         })
         .catch(() => {
-          new Flash(__('Something went wrong while deleting the source branch. Please try again.')); // eslint-disable-line
+          createFlash({
+            message: __('Something went wrong while deleting the source branch. Please try again.'),
+          });
         });
     },
   },