Fix not showing custom emojis in share page emoji picker (mastodon#9970)

Author: rinsuki

app/javascript/mastodon/containers/compose_container.js

@@ -7,6 +7,7 @@ import { IntlProvider, addLocaleData } from 'react-intl';
 import { getLocale } from '../locales';
 import Compose from '../features/standalone/compose';
 import initialState from '../initial_state';
+import { fetchCustomEmojis } from '../actions/custom_emojis';
 
 const { localeData, messages } = getLocale();
 addLocaleData(localeData);
@@ -17,6 +18,8 @@ if (initialState) {
   store.dispatch(hydrateStore(initialState));
 }
 
+store.dispatch(fetchCustomEmojis());
+
 export default class TimelineContainer extends React.PureComponent {
 
   static propTypes = {