Fix a pool management problem in ra_dav's replay implementation.
Fix a pool management problem in ra_dav's replay implementation.

* subversion/libsvn_ra_dav/replay.c
  (start_element): Stop destroying the file pool at the start of a new
   directory, it was already destroyed when the last directory pool was
   destroyed at the end of the previous directory, and destroying it
   twice is bad.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@859453 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion