PR c++/15664, c++/18276
	* pt.c (tsubst_decl) <TEMPLATE_DECL case>: Reorganize.  Correctly
	tsubst TEMPLATE_DECL that is a TEMPLATE_TEMPLATE_PARM.

	* g++.dg/template/ttp13.C: New test.
	* g++.dg/template/ttp14.C: Likewise.

From-SVN: r91633