Revert part of r946661.
Revert part of r946661.

* subversion/libsvn_wc/adm_crawler.c
  (report_revisions_and_depths): Stop reporting external information
   for nodes that aren't in the BASE tree, restoring pre-r946661 behaviour
   of the crawler. The plan is to eventually remove the externals callback
   from the base crawler entirely, and introduce a separate externals
   crawling API instead.

Suggested by: rhuijben

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