Revert "autoscroll emoji suggestions box"

This reverts commit 640740eeac.

app/javascript/mastodon/components/autosuggest_textarea.js

@@ -151,15 +151,6 @@ export default class AutosuggestTextarea extends ImmutablePureComponent {
     }
   }
 
-  componentDidUpdate () {
-    if (this.refs.selected) {
-      if (this.refs.selected.scrollIntoViewIfNeeded)
-        this.refs.selected.scrollIntoViewIfNeeded();
-      else
-        this.refs.selected.scrollIntoView({ behavior: 'auto', block: 'nearest' });
-    }
-  }
-
   render () {
     const { value, suggestions, disabled, placeholder, onKeyUp, autoFocus } = this.props;
     const { suggestionsHidden, selectedSuggestion } = this.state;
@@ -192,7 +183,6 @@ export default class AutosuggestTextarea extends ImmutablePureComponent {
         <div className={`autosuggest-textarea__suggestions ${suggestionsHidden || suggestions.isEmpty() ? '' : 'autosuggest-textarea__suggestions--visible'}`}>
           {suggestions.map((suggestion, i) => (
             <div
-              ref={i === selectedSuggestion ? 'selected' : null}
               role='button'
               tabIndex='0'
               key={suggestion}