Add loading indicator for trending tags (#7693)

app/javascript/mastodon/features/getting_started/containers/trends_container.js

@@ -0,0 +1,15 @@
+import { connect } from 'react-redux';
+import { injectIntl } from 'react-intl';
+import { fetchTrends } from '../../../actions/trends';
+import Trends from '../components/trends';
+
+const mapStateToProps = state => ({
+  trends: state.getIn(['trends', 'items']),
+  loading: state.getIn(['trends', 'isLoading']),
+});
+
+const mapDispatchToProps = dispatch => ({
+  fetchTrends: () => dispatch(fetchTrends()),
+});
+
+export default injectIntl(connect(mapStateToProps, mapDispatchToProps)(Trends));