re PR libstdc++/59247 (Bootstrap fails due to errors in libstdc++ sources with `...

re PR libstdc++/59247 (Bootstrap fails due to errors in libstdc++ sources with `--enable-symvers=gnu-versioned-namespace')

	PR libstdc++/59247
	* include/bits/c++config (_GLIBCXX_INLINE_VERSION): Declare namespace
	std::experimental::__7 as inline.
	* include/bits/regex.h (_GLIBCXX_BEGIN_NAMESPACE_VERSION): Do not
	enclose namespace __detail.
	* include/bits/regex.tcc (_GLIBCXX_BEGIN_NAMESPACE_VERSION): Likewise.
	* include/std/iomanip (_GLIBCXX_BEGIN_NAMESPACE_VERSION): Likewise.
	* include/ext/pb_ds/tag_and_trait.hpp (detail): Fix comment.
	* testsuite/ext/profile/mutex_extensions_neg.cc: Adjust line number.

From-SVN: r205277