Sync: Turn DCHECK into a warning.

This DCHECK is frequently encountered when full history sync is
enabled, and since the case appears to be properly handled, it
shouldn't be a DCHECK anyways.

BUG=229901

Review URL: https://codereview.chromium.org/14229002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@194856 0039d316-1c4b-4281-b951-d872f2087c98

sync/engine/syncer_util.cc

@@ -630,8 +630,8 @@ VerifyResult VerifyUndelete(syncable::WriteTransaction* trans,
   // Move the old one aside and start over.  It's too tricky to get the old one
   // back into a state that would pass CheckTreeInvariants().
   if (target->Get(IS_DEL)) {
-    DCHECK(target->Get(UNIQUE_CLIENT_TAG).empty())
-        << "Doing move-aside undeletion on client-tagged item.";
+    if (target->Get(UNIQUE_CLIENT_TAG).empty())
+      LOG(WARNING) << "Doing move-aside undeletion on client-tagged item.";
     target->Put(ID, trans->directory()->NextId());
     target->Put(UNIQUE_CLIENT_TAG, std::string());
     target->Put(BASE_VERSION, CHANGES_VERSION);