make new syncer thread the default.

chrome/browser/sync/sessions/sync_session_context.cc

Index: chrome/browser/sync/sessions/sync_session_context.cc
diff --git a/chrome/browser/sync/sessions/sync_session_context.cc b/chrome/browser/sync/sessions/sync_session_context.cc
index b5f072b9a8d76c78150fa144770cbe7ec0b149d4..f0cbce4ed2375072bf0de5d140249543e8286096 100644
--- a/chrome/browser/sync/sessions/sync_session_context.cc
+++ b/chrome/browser/sync/sessions/sync_session_context.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -36,10 +36,5 @@ SyncSessionContext::~SyncSessionContext() {
   }
 }
 
-void SyncSessionContext::set_last_snapshot(
-    const SyncSessionSnapshot& snapshot) {
-  previous_session_snapshot_.reset(new SyncSessionSnapshot(snapshot));
-}
-
 }  // namespace sessions
 }  // namespace browser_sync