Changed diff tree filtering to path

Previously it was using name which could make it hard
to filter for the file you want in a certain folder.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/53781

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

@@ -35,7 +35,7 @@ export default {
 
       if (search === '') return this.renderTreeList ? this.tree : this.allBlobs;
 
-      return this.allBlobs.filter(f => f.name.toLowerCase().indexOf(search) >= 0);
+      return this.allBlobs.filter(f => f.path.toLowerCase().indexOf(search) >= 0);
     },
     rowDisplayTextKey() {
       if (this.renderTreeList && this.search.trim() === '') {

changelogs/unreleased/mr-tree-filter-path-name.yml

+---
+title: Changed merge request filtering to be by path instead of name
+merge_request:
+author:
+type: changed

spec/javascripts/diffs/components/tree_list_spec.js

@@ -81,7 +81,7 @@ describe('Diffs tree list component', () => {
     });
 
     it('filters tree list to blobs matching search', done => {
-      vm.search = 'index';
+      vm.search = 'app/index';
 
       vm.$nextTick(() => {
         expect(vm.$el.querySelectorAll('.file-row').length).toBe(1);