Re-apply r990574 from the performance branch.
Re-apply r990574 from the performance branch.

* subversion/libsvn_subr/cache-inprocess.c
  (inprocess_cache_get_partial): 
   actually pass the data size to the serializer

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