posix.cc (_Jv_platform_nanotime): Return nanoseconds, not microseconds; use gettimeofday when available.

	* posix.cc (_Jv_platform_nanotime): Return nanoseconds, not
	microseconds; use gettimeofday when available.
	* posix-threads.cc (_Jv_CondWait): Improve accuracy and range of
	timeout calculation.
	* testsuite/libjava.lang/Thread_Sleep_2.java: New.
	* testsuite/libjava.lang/Thread_Sleep_2.out: New.
	* testsuite/libjava.lang/Thread_Sleep_2.xfail: New.

From-SVN: r116941