Merged from stable.

Merged from stable.

Sat Jul 12 15:28:26 2003  Kristian Rietveld  <kris@gtk.org>

	Merged from stable.

	This patch really really fixes scrolling. Related bugs: #81627,
	testcase provided by Timo Sirainen, #111500, testcase provided by
	manu, #113241, reported by Pedro Gimeno/Michael Natterer.

	*  gtk/gtktreeview.c (validate_visible_area): scrolling to a dy
	which is equal to the lower border of the window means scrolling
	to an invisible row, always update the dy when scrolling to an
	invisible row, corrected area_above/below calculations for
	invisible rows, when walking the tree correct the size
	subtracted for invalidated rows, fix wrong logic in comment.