merge revision(s) 36926:
* thread.c (rb_mutex_lock): stop multiple threads use pthread_cond_timedwait() concurrently. [Bug #6278] [ruby-core:44275]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_3@36928 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merge revision(s) 36926:
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_3@36928 b2dd03c8-39d4-4d8f-98ff-823fe69b080e