Update the autogroup summary visibility on notification changes

 The default visibility for the autogroup summary is private, except if there is at least
 one child notification with public visibility.

Flag: com.android.server.notification.autogroup_summary_icon_update
Test: atest GroupHelperTest
Bug: 309096654
Change-Id: I6d200abf57f341a98f2a4b1876e03347dd4ac079
4 files changed