getDropAction() was removed since it was thought that it may prevent future attempts at allowing the developer to choose a drop action. By reflecting on how future API may look, we've realized this is not the case. It can therefore be put back into the code.
Also, now that this is fixed, we can solve a problem I've discovered with text DnD. The problem is that when dragging from and to the same text component, nothing happens when dropping into the area of text that was selected for the drag. This is correct for moves, but the wrong thing for copies. This can now be remedied.