re PR c++/8572 (ICE with external definition of conversion operator to internal class within template class)

cp:
	PR c++/8572
	* cp-tree.h (grokoptypename): Add SCOPE parameter.
	* decl2.c (grokoptypename): Add SCOPE parameter. tsubst the type
	if in a template scope.
	* parse.y (unoperator): Return the scope.
	(operator_name): Adjust grokoptypename call.
testsuite:
	* g++.dg/parse/conv_op1.C: New test.

From-SVN: r60416