[INTERNAL] ListItemBase: mark the onfocusin event
[INTERNAL] ListItemBase: mark the onfocusin event

In cases where there is next List and ListItems, when the focus is set
on the inner list's listitem, the onfocusin was bubbling up the parent
list causing unexpected scrolling issue when sticky is enabled on the
outermost list control. To prevent this the onfocusin event is marked.
BCP: 2180375505

Change-Id: If759313a8d266aef2493d30f91bd8f9a0504a8a9

SAP/openui5,SAP/openui5,SAP/openui5,SAP/openui5