[Glitch] Only consider mouse move in scrolling on item insertion

Port cc1f13dfd0 to glitch-soc

app/javascript/flavours/glitch/components/scrollable_list.js

@@ -145,7 +145,7 @@ export default class ScrollableList extends PureComponent {
     const someItemInserted = React.Children.count(prevProps.children) > 0 &&
       React.Children.count(prevProps.children) < React.Children.count(this.props.children) &&
       this.getFirstChildKey(prevProps) !== this.getFirstChildKey(this.props);
-    if ((someItemInserted && this.node.scrollTop > 0) || this.mouseMovedRecently) {
+    if (someItemInserted && (this.node.scrollTop > 0 || this.mouseMovedRecently)) {
       return this.node.scrollHeight - this.node.scrollTop;
     } else {
       return null;