Logspam started during 0.4.9-dev'ing when zipfldr got committed,
logspam became much worse by 0.4.10-dev-599-g 932df378bf
But the actual bug of 'calling those functions when not needed' is much older than that.
Fix picked from 0.4.15-dev-3275-g cee171f5d2
Set the view object as the site of the drop target.
Implement GetItemPosition, SelectAndPositionItems, IsDropOnSource, GetDragPoint.
Use DROPEFFECT_COPY only when the item supports it.
CDefView: Make GetItemObject return an IContectMenu after setting itself as the site.
CDefViewBckgrndMenu: Make the inner context menu use the same site. Implement handling CMDSTR_VIEWLISTA and CMDSTR_VIEWDETAILSA.
CDefaultContextMenu: CMDSTR_VIEWLISTA and CMDSTR_VIEWDETAILSA shouldn't be handled in this class.
Fixes CORE-14327 and the two buttons that change the view mode
