Revision 1683544

Minor FSFS optimization: do not read 'current' file on FS open to save
cached youngest revision. Current API users often call 
svn_fs_youngest() right after svn_fs_open() which cause 'current' file 
read again.

* subversion/libsvn_fs_fs/fs_fs.c
  (svn_fs_fs__open): Do not call get_youngest(). Just initialize
   ffd->youngest_rev_cache to zero.