Activity event displayed on space dashboard when deleting a photo gallery present a link to the deleted gallery

This is due to the fact the "page" field of the activity is wrong, it is stored as "Space_spacename_Photos.WebHome" instead of "Space_spacename_Photos.GalleryName", while the URL is correctly stored. The macro displaying the activity event check if $xwiki.exists($event.page)) and thus make the link appear.
This appen only for deletion events, creation and modification are ok.