Allow propeties to be reverted by ensuring the things we are removing or replacing are writeable.
Allow propeties to be reverted by ensuring the things we are removing or
replacing are writeable.

* subversion/libsvn_wc/adm_ops.c (revert_admin_things) : Set property files
  writeable before trying to remove or replace them.

Note that we need a regression test to test reverting properties.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@841453 13f79535-47bb-0310-9956-ffa450edef68

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