* AddItem() versions did not work correctly at all: maximum insertion index

was limited by the visible list count, it did not care if the insertion
  failed, it didn't maintain the BListItem::fHasSubitems field, neither
  fVisible, and it didn't invalidate the latch of the parent, if needed.
* The "add item at end" also did not care if the item should be added to the
  visible list, too, it always did.
* AddUnder() would have crashed with a NULL superitem.
* _RemoveItem() now updates the fHasSubitems field as well.
* _SuperitemForIndex() can now return the index of the superitem as well.
* SortItemsUnder() did not check if the "underItem" if the items should be
  added to the visible list or not, it also just did.
* SortItemsUnder() now invalidates the part of the visible list that may
  have been changed.
* This fixed bug #662, and possibly #663, too (at least I could never
  reproduce it).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@17812 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/interface/OutlineListView.h

@@ -126,8 +126,9 @@ class BOutlineListView : public BListView {
 		bool				OutlineMoveItem(int32 from, int32 to);
 		bool				OutlineReplaceItem(int32 index, BListItem* item);
 		void				CommonMoveItems(int32 from, int32 count, int32 to);
-		BListItem*			SuperitemForIndex(int32 fullListIndex, int32 level);
-		int32				FindPreviousVisibleIndex(int32 fullListIndex);
+		BListItem*			_SuperitemForIndex(int32 fullListIndex, int32 level,
+								int32* _superIndex = NULL);
+		int32				_FindPreviousVisibleIndex(int32 fullListIndex);
 
 	private:
 		BList				fFullList;