hashtable_policy.h (_Prime_rehash_policy): Remove automatic shrink.

hashtable_policy.h (_Prime_rehash_policy): Remove automatic shrink.

2012-11-16  François Dumont  <fdumont@gcc.gnu.org>

	* include/bits/hashtable_policy.h (_Prime_rehash_policy): Remove
	automatic shrink.
	(_Prime_rehash_policy::_M_bkt_for_elements): Do not call
	_M_next_bkt anymore.
	(_Prime_rehash_policy::_M_next_bkt): Move usage of
	_S_growth_factor ...
	(_Prime_rehash_policy::_M_need_rehash): ... here.
	* include/bits/hashtable.h (_Hashtable<>): Adapt.
	* testsuite/performance/23_containers/insert_erase/41975.cc: Add
	_USE_TR1 to force build using std::tr1 container.
	* testsuite/performance/23_containers/insert/unordered_set.cc:
	Likewise.
	* testsuite/performance/23_containers/insert/54075.cc: New.

From-SVN: r193576