Use React.PureComponent instead of React.Component (#6653)

app/javascript/mastodon/features/notifications/components/clear_column_button.js

@@ -2,7 +2,7 @@ import React from 'react';
 import PropTypes from 'prop-types';
 import { FormattedMessage } from 'react-intl';
 
-export default class ClearColumnButton extends React.Component {
+export default class ClearColumnButton extends React.PureComponent {
 
   static propTypes = {
     onClick: PropTypes.func.isRequired,

app/javascript/mastodon/features/ui/components/bundle.js

@@ -4,7 +4,7 @@ import PropTypes from 'prop-types';
 const emptyComponent = () => null;
 const noop = () => { };
 
-class Bundle extends React.Component {
+class Bundle extends React.PureComponent {
 
   static propTypes = {
     fetchComponent: PropTypes.func.isRequired,

app/javascript/mastodon/features/ui/components/bundle_column_error.js

@@ -13,7 +13,7 @@ const messages = defineMessages({
   retry: { id: 'bundle_column_error.retry', defaultMessage: 'Try again' },
 });
 
-class BundleColumnError extends React.Component {
+class BundleColumnError extends React.PureComponent {
 
   static propTypes = {
     onRetry: PropTypes.func.isRequired,

app/javascript/mastodon/features/ui/components/bundle_modal_error.js

@@ -10,7 +10,7 @@ const messages = defineMessages({
   close: { id: 'bundle_modal_error.close', defaultMessage: 'Close' },
 });
 
-class BundleModalError extends React.Component {
+class BundleModalError extends React.PureComponent {
 
   static propTypes = {
     onRetry: PropTypes.func.isRequired,