Fix the expander regression with async inflation

Add an update of expand status to fix the issue that when we update a
group summary notification, the group header's expand status was
reset to not expanded.

Fix: 339868658
Test: manual, follow the steps under the bug
Flag: ACONFIG notification_async_group_header_inflation TRUNK_FOOD
Change-Id: I1f24b0292c3115d09f457466461177808f625e2b