Fixes diff tree list not working

This fixes the diff tree list not working after the user has
used the browsers find on page function.

app/assets/javascripts/diffs/components/app.vue

@@ -172,7 +172,6 @@ export default {
       treeWidth,
       diffFilesLength: 0,
       virtualScrollCurrentIndex: -1,
-      disableVirtualScroller: false,
     };
   },
   computed: {
@@ -414,6 +413,7 @@ export default {
       'setShowTreeList',
       'navigateToDiffFileIndex',
       'setFileByFile',
+      'disableVirtualScroller',
     ]),
     subscribeToEvents() {
       notesEventHub.$once('fetchDiffData', this.fetchData);
@@ -522,11 +522,11 @@ export default {
             // To make sure the user is using the find function we need to wait for blur
             // and max 1000ms to be sure it the search box is filtered
             if (delta >= 0 && delta < 1000) {
-              this.disableVirtualScroller = true;
+              this.disableVirtualScroller();
 
               if (window.gon?.features?.diffSearchingUsageData) {
                 api.trackRedisHllUserEvent('i_code_review_user_searches_diff');
-                api.trackRedisCounterEvent('user_searches_diffs');
+                api.trackRedisCounterEvent('diff_searches');
               }
             }
           }
@@ -651,7 +651,7 @@ export default {
           <div v-if="isBatchLoading" class="loading"><gl-loading-icon size="lg" /></div>
           <template v-else-if="renderDiffFiles">
             <dynamic-scroller
-              v-if="!disableVirtualScroller && isVirtualScrollingEnabled"
+              v-if="isVirtualScrollingEnabled"
               ref="virtualScroller"
               :items="diffs"
               :min-item-size="70"

app/assets/javascripts/diffs/store/actions.js

@@ -520,14 +520,14 @@ export const toggleActiveFileByHash = ({ commit }, hash) => {
   commit(types.VIEW_DIFF_FILE, hash);
 };
 
-export const scrollToFile = ({ state, commit }, path) => {
+export const scrollToFile = ({ state, commit, getters }, path) => {
   if (!state.treeEntries[path]) return;
 
   const { fileHash } = state.treeEntries[path];
 
   commit(types.VIEW_DIFF_FILE, fileHash);
 
-  if (window.gon?.features?.diffsVirtualScrolling) {
+  if (getters.isVirtualScrollingEnabled) {
     eventHub.$emit('scrollToFileHash', fileHash);
 
     setTimeout(() => {
@@ -535,6 +535,10 @@ export const scrollToFile = ({ state, commit }, path) => {
     });
   } else {
     document.location.hash = fileHash;
+
+    setTimeout(() => {
+      handleLocationHash();
+    });
   }
 };
 
@@ -844,3 +848,5 @@ export function reviewFile({ commit, state }, { file, reviewed = true }) {
   setReviewsForMergeRequest(mrPath, reviews);
   commit(types.SET_MR_FILE_REVIEWS, reviews);
 }
+
+export const disableVirtualScroller = ({ commit }) => commit(types.DISABLE_VIRTUAL_SCROLLING);

app/assets/javascripts/diffs/store/getters.js

@@ -177,6 +177,10 @@ export function suggestionCommitMessage(state, _, rootState) {
 export const isVirtualScrollingEnabled = (state) => {
   const vSrollerCookie = Cookies.get('diffs_virtual_scrolling');
 
+  if (state.disableVirtualScroller) {
+    return false;
+  }
+
   if (vSrollerCookie) {
     return vSrollerCookie === 'true';
   }

app/assets/javascripts/diffs/store/modules/diff_state.js

@@ -43,4 +43,5 @@ export default () => ({
   defaultSuggestionCommitMessage: '',
   mrReviews: {},
   latestDiff: true,
+  disableVirtualScroller: false,
 });

app/assets/javascripts/diffs/store/mutation_types.js

@@ -47,3 +47,4 @@ export const SET_DIFF_FILE_VIEWER = 'SET_DIFF_FILE_VIEWER';
 export const SET_SHOW_SUGGEST_POPOVER = 'SET_SHOW_SUGGEST_POPOVER';
 
 export const TOGGLE_LINE_DISCUSSIONS = 'TOGGLE_LINE_DISCUSSIONS';
+export const DISABLE_VIRTUAL_SCROLLING = 'DISABLE_VIRTUAL_SCROLLING';

app/assets/javascripts/diffs/store/mutations.js

@@ -362,4 +362,7 @@ export default {
   [types.SET_MR_FILE_REVIEWS](state, newReviews) {
     state.mrReviews = newReviews;
   },
+  [types.DISABLE_VIRTUAL_SCROLLING](state) {
+    state.disableVirtualScroller = true;
+  },
 };

spec/frontend/diffs/store/actions_spec.js

@@ -874,6 +874,7 @@ describe('DiffsStoreActions', () => {
 
   describe('scrollToFile', () => {
     let commit;
+    const getters = { isVirtualScrollingEnabled: false };
 
     beforeEach(() => {
       commit = jest.fn();
@@ -888,7 +889,7 @@ describe('DiffsStoreActions', () => {
         },
       };
 
-      scrollToFile({ state, commit }, 'path');
+      scrollToFile({ state, commit, getters }, 'path');
 
       expect(document.location.hash).toBe('#test');
     });
@@ -902,7 +903,7 @@ describe('DiffsStoreActions', () => {
         },
       };
 
-      scrollToFile({ state, commit }, 'path');
+      scrollToFile({ state, commit, getters }, 'path');
 
       expect(commit).toHaveBeenCalledWith(types.VIEW_DIFF_FILE, 'test');
     });