improve seed generation in java.util.Random
improve seed generation in java.util.Random

The previous code caused frequent seed collisions for successive calls
to the no-arg constructor, even for single threaded workloads.  This
patch should avoid such collisions in both single and multi-threaded
cases.

getlantern/avian,getlantern/avian,lwahlmeier/avian,lostdj/avian,joshuawarner32/avian,marcinolawski/avian,minor-jason/avian,dicej/avian,ucdseniordesign/avian,lostdj/avian,marcinolawski/avian,dicej/avian,lostdj/avian,bigfatbrowncat/avian-pack.avian,ucdseniordesign/avian,minor-jason/avian,bgould/avian,lwahlmeier/avian,lwahlmeier/avian,MaartenR/avian,bgould/avian,bgould/avian,getlantern/avian,joshuawarner32/avian,MaartenR/avian,bigfatbrowncat/avian-pack.avian,minor-jason/avian,dicej/avian,joshuawarner32/avian,minor-jason/avian,ucdseniordesign/avian,joshuawarner32/avian,marcinolawski/avian,lwahlmeier/avian,lostdj/avian,getlantern/avian,bigfatbrowncat/avian-pack.avian,MaartenR/avian,marcinolawski/avian,dicej/avian,bigfatbrowncat/avian-pack.avian,MaartenR/avian,ucdseniordesign/avian,bgould/avian