Previously, datagrids would attach additional event handler for

infoboxes on top of the initial event handler. This would result in two

fetches for all infoboxes in the datagrid until the first refresh. Now

we set an attribute on elements which can have infoboxes attached them

when the infobox handler has been added so that it will not be added

again.

Verified infoboxes in datagrids are no longer requested twice.