Fix "svn diff --summarize" to stop printing the path twice. (It was printing
e.g. "path/to/file/path/to/file".)

### This also makes it omit the prefix of URLs, which is not good.
### Normal diff does its prefix stuff differently: optional relative_to_dir
### parameter can be used to suppress a leading path part, but otherwise
### it already gives a relative path or absolute URL, just as invoked.
### Can summarize do the same?

* subversion/svn/diff-cmd.c
  (summarize_xml, summarize_regular): Stop appending the path passed in via
    the baton. Document that the baton is no longer used.
  (svn_cl__diff): Stop passing a path for the baton argument of the two
    summarize functions. (This also clears a "casting away 'const' warning.)

Index: subversion/svn/diff-cmd.c
===================================================================
--- subversion/svn/diff-cmd.c	(revision 33600)
+++ subversion/svn/diff-cmd.c	(working copy)
@@ -71,24 +71,16 @@
     }
 }
 
-/* Print summary information about a given change as XML, implements the
- * svn_client_diff_summarize_func_t interface. The @a baton is a 'char *'
- * representing the either the path to the working copy root or the url
- * the path the working copy root corresponds to. */
+/* Print summary information about a given change as XML. Implements the
+ * svn_client_diff_summarize_func_t interface. BATON is not used. */
 static svn_error_t *
 summarize_xml(const svn_client_diff_summarize_t *summary,
-                   void *baton,
-                   apr_pool_t *pool)
+              void *baton,
+              apr_pool_t *pool)
 {
-  /* Full path to the object being diffed.  This is created by taking the
-   * baton, and appending the target's relative path. */
-  const char *path = baton;
+  const char *path = summary->path;
   svn_stringbuf_t *sb = svn_stringbuf_create("", pool);
 
-  /* Tack on the target path, so we can differentiate between different parts
-   * of the output when we're given multiple targets. */
-  path = svn_path_join(path, summary->path, pool);
-
   /* Convert non-urls to local style, so that things like "" show up as "." */
   if (! svn_path_is_url(path))
     path = svn_path_local_style(path, pool);
@@ -105,18 +97,14 @@
   return svn_cl__error_checked_fputs(sb->data, stdout);
 }
 
-/* Print summary information about a given change, implements the
- * svn_client_diff_summarize_func_t interface. */
+/* Print summary information about a given change. Implements the
+ * svn_client_diff_summarize_func_t interface. BATON is not used. */
 static svn_error_t *
 summarize_regular(const svn_client_diff_summarize_t *summary,
-               void *baton,
-               apr_pool_t *pool)
+                  void *baton,
+                  apr_pool_t *pool)
 {
-  const char *path = baton;
-
-  /* Tack on the target path, so we can differentiate between different parts
-   * of the output when we're given multiple targets. */
-  path = svn_path_join(path, summary->path, pool);
+  const char *path = summary->path;
 
   /* Convert non-urls to local style, so that things like "" show up as "." */
   if (! svn_path_is_url(path))
@@ -323,8 +311,7 @@
                      opt_state->depth,
                      opt_state->notice_ancestry ? FALSE : TRUE,
                      opt_state->changelists,
-                     summarize_func,
-                     (void *) target1,
+                     summarize_func, NULL,
                      ctx, iterpool));
           else
             SVN_ERR(svn_client_diff4
@@ -367,8 +354,7 @@
                      opt_state->depth,
                      opt_state->notice_ancestry ? FALSE : TRUE,
                      opt_state->changelists,
-                     summarize_func,
-                     (void *) truepath,
+                     summarize_func, NULL,
                      ctx, iterpool));
           else
             SVN_ERR(svn_client_diff_peg4