Merge branch 'es-class-syntax' into 'master'

app/assets/javascripts/diff.js

app/assets/javascripts/dispatcher.js

app/assets/javascripts/issuable_form.js

app/assets/javascripts/issue.js

app/assets/javascripts/issue_show/components/description.vue

app/assets/javascripts/main.js

app/assets/javascripts/merge_request.js

app/assets/javascripts/notes.js

app/assets/javascripts/project_new.js

app/assets/javascripts/signin_tabs_memoizer.js

app/assets/javascripts/single_file_diff.js

app/assets/javascripts/snippets_list.js

app/assets/javascripts/star.js

app/assets/javascripts/subscription_select.js

app/assets/javascripts/task_list.js

app/assets/javascripts/todos.js

app/assets/javascripts/tree.js

app/assets/javascripts/usage_ping.js

app/assets/javascripts/user.js

app/assets/javascripts/user_tabs.js