2004-03-20  Sven Neumann  <sven@gimp.org>

	* app/widgets/gimppropwidgets.c (gimp_prop_size_entry_callback):
	avoid to set the unit property with every size change; only set it
	if it actually changed.

	* app/core/gimpimage-undo-push.c (gimp_image_undo_push_text_layer):
	allow to pass a GParamSpec that identifies a single text property
	to be changed. In this case, don't store a GimpText object on the
	undo stack but only the changed value.

	* app/tools/gimptexttool.c: use the new undo feature to reduce the
	memory footprint of text undo for the common case.

	* app/text/gimptextlayer.c: changed accordingly.