Use static pointer to member when catching nullptr

Use static pointer to member when catching nullptr

libstdc++-v3:

	* libsupc++/pbase_type_info.cc (__pbase_type_info::__do_catch): Use
	static objects for catching nullptr as pointer to member types.

gcc/testsuite:

	* g++.dg/cpp0x/nullptr35.C: Change expected result for catching as
	pointer to member function and also test catching by reference.

From-SVN: r238532