tree.c (mapcar): When dealing with a DECL, use it's constant value, if any.

tree.c (mapcar): When dealing with a DECL, use it's constant value, if any.

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	* tree.c (mapcar): When dealing with a DECL, use it's constant
	value, if any.
	* pt.c (lookup_template_class): Don't mangle the names of template
	classes whose arguments are unknown.
	* pt.c (tsubst_expr): Handle GOTO_STMT correctly.

From-SVN: r18803