2007-09-29 Emmanuel Pacaud <emmanuel.pacaud@lapp.in2p3.fr>

	Duplicate the GogGraph object used by the graph dialog. That's needed
	because GOGraphWidget change the width and height property of it's
	graph model on every resize, which breaks the SheetObjectGraph.

	* src/gnm-graph-window.c (gnm_graph_window_set_graph): duplicate
	graph.
	(gnm_graph_window_new): add a safety check on graph parameter.

svn path=/trunk/; revision=15944