hrtime regression #4751

I have the feeling 89f056b introduced a regression. The nanoseconds might return negative values if you compare the actual value with the one before. This does not occur in 5.3 or before.

> process.hrtime(t)
[ 45, 373756947 ]
> process.hrtime(t)
[ 46, -1831860 ]

Easy to reproduce with:

var t = process.hrtime(); while(t[1] > 0) t = process.hrtime(t);