The drop location should be tracked in terms of the position
where new data should be inserted. For components that manage
a list of items (list and tree for example), the drop location
should indicate the index where new data should be inserted.
For text components the location should represent a position
between characters. For components that manage tabular data
(table for example), the drop location should indicate
where to insert new rows, columns, or both, to accommodate
the dropped data.