Lazy load css for legacy themes

Author: KoolADE85

src/lib/components/AgGrid.react.js

@@ -103,11 +103,11 @@ function DashAgGrid(props) {
 
  const shouldLoadLegacyCSS = useMemo(() => {
  // Only load legacy CSS if theme is 'legacy' or unset
+ const dashGridOptions = props.dashGridOptions || {};
  return (
- !('theme' in props.dashGridOptions) ||
- props.dashGridOptions.theme === 'legacy'
+ !('theme' in dashGridOptions) || dashGridOptions.theme === 'legacy'
  );
- }, [props.dashGridOptions.theme]);
+ }, [props.dashGridOptions]);
 
  const LegacyThemeLoader = useMemo(() => {
  if (