Cleanup a bit more response checks found when doing the r1554019
handler cleanup.

* subversion/libsvn_ra_serf/commit.c
  (close_edit): Replace assertion by proper error. Clear
    activity url before/on delete to avoid trying another delete
    on failure of the delete.

* subversion/libsvn_ra_serf/inherited_props.c
  (svn_ra_serf__get_inherited_props): Expect strict result code.

* subversion/libsvn_ra_serf/options.c
  (svn_ra_serf__v2_get_youngest_revnum): Replace assertion by proper
    error by moving a bit of code from get_baseline_info here.

* subversion/libsvn_ra_serf/property.c
  (retrieve_baseline_info): Check if we really get a revision.
  (get_baseline_info): Remove check that is now in
    svn_ra_serf__v2_get_youngest_revnum.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1554021 13f79535-47bb-0310-9956-ffa450edef68