backport r32050 by akr
- lib/securerandom.rb (SecureRandom.random_bytes): modify PRNG state to prevent random number sequence repeatation at forked child process which has same pid. reported by Eric Wong.
backport r32124 by nahi
- test/test_securerandom.rb: Add testcase. This testcase does NOT aim to test cryptographically strongness and randomness. It includes the test for PID recycle issue of OpenSSL described in #4579 but it's disabled by default.