array.c: improve Array#sample
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57380 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
array.c: improve Array#sample
from a large array. based on the patch by tomoya ishida
in [ruby-dev:49956]. [Bug #13136]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57380 b2dd03c8-39d4-4d8f-98ff-823fe69b080e