c++: clean up ref-extended temp on throwing dtor [PR53868]

c++: clean up ref-extended temp on throwing dtor [PR53868]

We have wrap_temporary_cleanups to handle the EH region nesting problems
between cleanups for complete variables and cleanups for temporaries used in
their construction, but we weren't calling it for temporaries extended from
binding to a reference.

We still don't want this for array cleanups (since my PR94041 fix), so I
move that exception from initialize_local_var to wrap_temporary_cleanups.

	PR c++/53868

gcc/cp/ChangeLog:

	* decl.c (cp_finish_decl): Use wrap_temporary_cleanups for
	cleanups from set_up_extended_ref_temp.
	(wrap_temporary_cleanups): Ignore array cleanups.
	(initialize_local_var): Don't check for array here.
	* cp-tree.h (BIND_EXPR_VEC_DTOR): New.
	* init.c (build_vec_delete_1): Set it.

gcc/testsuite/ChangeLog:

	* g++.dg/eh/ref-temp1.C: New test.
	* g++.dg/eh/ref-temp2.C: New test.