[Sync] Replace uses of ObserverListThreadSafe with WeakHandles

chrome/browser/sync/engine/syncer_unittest.cc

 // 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.
 //
 // Syncer unit tests. Unfortunately a lot of these tests
 // are outdated and need to be reworked and updated.
 
 #include <algorithm>
 #include <limits>
 #include <list>
 #include <map>
 #include <set>
 #include <string>
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/location.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/message_loop.h"
 #include "base/string_number_conversions.h"
 #include "base/stringprintf.h"
 #include "base/time.h"
 #include "build/build_config.h"
 #include "chrome/browser/sync/engine/conflict_resolver.h"
 #include "chrome/browser/sync/engine/get_commit_ids_command.h"
 #include "chrome/browser/sync/engine/model_safe_worker.h"
 #include "chrome/browser/sync/engine/net/server_connection_manager.h"
 #include "chrome/browser/sync/engine/process_updates_command.h"
 #include "chrome/browser/sync/engine/nigori_util.h"
@@ skipping 432 matching lines @@
   }
 
   bool Get(int64 metahandle, syncable::IsDelField field) const {
     return GetField(metahandle, field, false);
   }
 
   bool Get(int64 metahandle, syncable::BitField field) const {
     return GetField(metahandle, field, false);
   }
 
+  MessageLoop message_loop_;
+
   // Some ids to aid tests. Only the root one's value is specific. The rest
   // are named for test clarity.
   // TODO(chron): Get rid of these inbuilt IDs. They only make it
   // more confusing.
   syncable::Id root_id_;
   syncable::Id parent_id_;
   syncable::Id child_id_;
 
   TestIdFactory ids_;
 
@@ skipping 4817 matching lines @@
   Add(low_id_);
   Add(high_id_);
   SyncShareAsDelegate();
   ExpectLocalOrderIsByServerId();
 }
 
 const SyncerTest::CommitOrderingTest
 SyncerTest::CommitOrderingTest::LAST_COMMIT_ITEM = {-1, TestIdFactory::root()};
 
 }  // namespace browser_sync