Update the hash table of active script pids even on paths where a

script process wasn't created (storing 0 for the pid in that case).
Otherwise, the remembered pid is that of the last successful script
execution for this hash key.

Prior to this patch, the wrong process could be terminated in
rare circumstances:

- A CGI process with pid 10101 is forked for connection 99.

- After the CGI exits and some time elapses, some other process gets 
  pid 10101. (Connection 99 hasn't handled another CGI request yet.)

- The next time connection 99 has a CGI process, the fork()
  or other early setup fails, so no CGI process is created.

- The remembered pid for connection 99 is still 10101.  It
  gets terminated (subject to permissions).


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@503340 13f79535-47bb-0310-9956-ffa450edef68