shared_ptr (__shared_ptr): Assert non-void pointer.

shared_ptr (__shared_ptr): Assert non-void pointer.

	* include/bits/shared_ptr (__shared_ptr): Assert non-void pointer.
	* include/bits/shared_ptr (default_delete): Likewise.
	* testsuite/20_util/shared_ptr/cons/58839.cc: Do not use
	default_delete<void>.
	* testsuite/20_util/shared_ptr/cons/void_neg.cc: New.
	* testsuite/20_util/default_delete/void_neg.cc: New.
	* testsuite/20_util/shared_ptr/cons/43820_neg.cc: Adjust line numbers.
	* testsuite/20_util/unique_ptr/assign/48635_neg.cc: Likewise.

From-SVN: r204225