Make an old migration a little more robust

Summary: See https://github.com/facebook/phabricator/pull/507

Test Plan: This is hard to test since the migration no longer runs against HEAD, but pull 507 strongly implies this is the correct fix.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D8837

resources/sql/patches/20131004.dxreviewers.php

@@ -29,6 +29,13 @@ foreach (new LiskMigrationIterator($table) as $revision) {
     ->setActor(PhabricatorUser::getOmnipotentUser());
 
   foreach ($reviewer_phids as $dst) {
+    if (phid_get_type($dst) == PhabricatorPHIDConstants::PHID_TYPE_UNKNOWN) {
+      // At least one old install ran into some issues here. Skip the row if we
+      // can't figure out what the destination PHID is. See here:
+      // https://github.com/facebook/phabricator/pull/507
+      continue;
+    }
+
     $editor->addEdge(
       $revision_phid,
       PhabricatorEdgeConfig::TYPE_DREV_HAS_REVIEWER,