* include/bits/random.h (random_device): Move implementation to...
	* src/c++11/random.cc: ...here.  New file.
	* config/abi/pre/gnu.ver: Add new version GLIBCXX_3.4.18.  Export
	std::random_device::* symbols.
	* config/abi/post/x86_64-linux-gnu/baseline_symbols.txt: Generated.
	* src/c++11/Makefile.am (sources): Add random.cc.
	* src/c++11/Makefile.in: Regenerated.

From-SVN: r190787