Trying to diagnose possibly random error.

Exception in thread "hg ...args...: stdout copier" java.lang.NullPointerException
        at hudson.util.StreamCopyThread.run(StreamCopyThread.java:58)


git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@28845 71c3de6d-444a-0410-be80-ed276b4c234a