2003-03-22  Michael Natterer  <mitch@gimp.org>

	* app/core/gimpdrawable-preview.c
	* app/core/gimpimage.c (get_preview_size): return square
	dimensions in config->layer_previews is FALSE (except if the size
	is requested for a popup).
	(get_popup_size): don't crete popups if config->layer_previews
	is FALSE.

	* app/core/gimpimage.c: added utility function
	gimp_image_previews_resize() and call it on "notify::layer-previews".
	Calls gimp_viewable_size_changed() on all drawables of the image
	and on the image itself. Ensures that drawable/image previews
	toggle their size correctly when toggling layer_previews.

	* app/widgets/gimpselectioneditor.c: create the selection preview
	as a popup so it keeps the image's aspect ratio when
	layer_previews is FALSE.