2008-08-17  Sven Neumann  <sven@gimp.org>

	Next step towards fixing bug #344818:

	* app/pdb/gimpprocedure.c (gimp_procedure_execute): if the error
	has not already been set, construct one from the error message
	that is optionally passed with the return values.

	* plug-ins/common/file-png.c: changed to pass an error message
	with the return values instead of calling g_message() in case of
	an error.


svn path=/trunk/; revision=26620