2004-03-14  Michael Natterer  <mitch@gimp.org>

	* app/core/gimpdrawable-offset.c (gimp_drawable_offset)
	* app/core/gimpdrawable.c (gimp_drawable_scale) (gimp_drawable_resize)
	* app/core/gimplayer.c (gimp_layer_convert) (gimp_layer_add_alpha):
	use gimp_drawable_set_tiles() instead of fiddling with
	drawable->tiles, ->bytes etc. manually.