2005-01-15  Michael Natterer  <mitch@gimp.org>

	* app/core/gimpchannel.c: implement GimpItem::convert(). Handles
	any drawable, including conversion to GRAY, flattening and
	resizing.

	* app/widgets/gimpchanneltreeview.c: implement dropping of all
	kinds of drawables as new channels. Fixes bug #158133.

	Simplified component dropping by removing stuff which is done by
	gimp_item_convert() now.