2004-09-27  Sven Neumann  <sven@gimp.org>

	* app/core/gimpimagefile.c: removed conversion to TempBuf.
	Instead implement GimpViewable::get_new_pixbuf by compositing the
	thumbnail on a checkerboard.

	* app/widgets/gimpviewrenderer.[ch]: renamed the no_view_pixbuf
	struct member to pixbuf.
	(gimp_view_renderer_real_render): try gimp_viewable_get_pixbuf()
	and render the pixbuf before falling back to the TempBuf preview.
	(gimp_view_renderer_render_pixbuf): new function that sets a
	pixbuf for the renderer and flushes the render_buffer.

	* app/widgets/gimpviewrendererimagefile.c
	(gimp_view_renderer_imagefile_render): render the pixbuf.

	* app/dialogs/dialogs-constructors.c: create the document history
	dockable with a zero borderwidth.