2006-10-14  Michael Natterer  <mitch@gimp.org>

	* app/dialogs/convert-dialog.c
	* app/dialogs/desaturate-dialog.c
	* app/dialogs/grid-dialog.c
	* app/dialogs/image-properties-dialog.c
	* app/dialogs/layer-add-mask-dialog.c
	* app/dialogs/layer-options-dialog.c
	* app/dialogs/print-size-dialog.c
	* app/dialogs/resize-dialog.c
	* app/dialogs/scale-dialog.c
	* app/dialogs/vectors-options-dialog.c: don't allow "context" to
	be NULL in any dialog constructor.