Fix ArcTool partition command error, a=chris

diff --git a/src/library/IndexDocumentBundle.php b/src/library/IndexDocumentBundle.php
index e9a816a4b..71b3ffce6 100644
--- a/src/library/IndexDocumentBundle.php
+++ b/src/library/IndexDocumentBundle.php
@@ -681,12 +681,12 @@ class IndexDocumentBundle implements CrawlConstants
         }
         if ($just_stats) {
             $term_stats = [];
-            foreach ($this->postings as $term => $posting) {
-                $posting_records = $postings_tools->unpack($posting);
+            foreach ($this->postings as $term => $postings) {
+                list($posting_records,) = $this->unpackPostings($postings);
                 $term_stats[$term] = count($posting_records);
             }
             $statistics = [
-                "NUM_DOCS" => count($this->doc_map),
+                "NUM_DOCS" => $this->doc_map_counter,
                 "NUM_LINKS" => $link_cnt,
                 "TERM_STATISTICS" => $term_stats
             ];