Print the failing seed in random-test just like random-combine-test does.

* subversion/tests/libsvn_delta/random-test.c
  (do_random_test): Renamed from random_test. Returns the last seed used.
  (random_test): New; wrapper for do_random_test, prints seed on failure.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1569378 13f79535-47bb-0310-9956-ffa450edef68