regex.h: Remove unnecessary friends.

regex.h: Remove unnecessary friends.

2013-10-26  Tim Shen  <timshen91@gmail.com>

	* include/bits/regex.h: Remove unnecessary friends.
	* include/bits/regex.tcc (__regex_algo_impl<>): Move __get_executor
	to here.
	* include/bits/regex_executor.h: Remove _DFSExecutor and _BFSExecutor;
	they are merged into _Executor. Eliminate quantifier tracking part, so
	it's faster.
	* include/bits/regex_executor.tcc: Implement _Executor.
	* testsuite/28_regex/algorithms/regex_match/ecma/char/ungreedy.cc: New.
	* testsuite/28_regex/algorithms/regex_search/ecma/greedy.cc: Adjust
	duplicate testcases.
	* testsuite/performance/28_regex/split.h: New.
	* testsuite/performance/28_regex/split_bfs.cc: New.
	* testsuite/util/testsuite_regex.h: Adjust behavior of two-executors
	agreement judger: do not compare match_results when executor return
	false.

From-SVN: r204093