On the fsx-id branch:  Instead wrapping svn_fs_path_change2_t in FSX'
change_t, expand its elements into change_t.  That way, we can replace
the svn_fs_id_t instance in it later.

Most of the code churn is due to the fact that there is one structure
level less now.

* subversion/libsvn_fs_x/fs.h
  (change_t): Expand the INFO sub-struct into this one.

* subversion/libsvn_fs_x/temp_serializer.c
  (serialize_change,
   deserialize_change): Remove INFO intermediary.

* subversion/libsvn_fs_x/changes.c
  (append_change,
   svn_fs_x__changes_get_list,
   svn_fs_x__changes_get_list_func): Use the CHANGE directly instead of
                                     the former INFO sub-structure.

* subversion/libsvn_fs_x/low_level.c
  (read_change,
   write_change_entry): Ditto.
  (svn_fs_x__write_changes): The hash now contains full change_t.

* subversion/libsvn_fs_x/transaction.h
  (svn_fs_x__paths_changed): Remove. The functionality has been moved
                             to tree.c

* subversion/libsvn_fs_x/transaction.c
  (path_change_dup): Duplicate a full change_t now.
  (fold_change): The hashes now contain full change_t, including the name.
                 There's no intermediate INFO struct level anymore. 
  (process_changes): There's no intermediate INFO struct level anymore.
  (svn_fs_x__paths_changed): Remove here. See x_paths_changed in tree.c
  (svn_fs_x__add_change,
   verify_locks): The hashes now contain full change_t.

* subversion/libsvn_fs_x/tree.c
  (construct_fs_path_change): New utility function converting our internal
                              change_t into the FS API level equivalent.
  (x_paths_changed): Convert changed paths lists from using change_t to
                     svn_fs_path_change2_t and the internal hash or array
                     to a hash as required by the API.

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/fsx-id@1648068 13f79535-47bb-0310-9956-ffa450edef68