Fix Win32/OSX failures of log sensitive tests log_tests.py 17, 19.
Fix Win32/OSX failures of log sensitive tests log_tests.py 17, 19.

* subversion/libsvn_repos/log.c
  (do_merged_log): Initialize svn_boolean_t changed since it is not
  guaranteed a value upon return from check_history().

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion