[Sync] Move ChangeRecord into its own file (change_record.{h,cc})

chrome/browser/sync/glue/sync_backend_host.h

 // 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.
 
 #ifndef CHROME_BROWSER_SYNC_GLUE_SYNC_BACKEND_HOST_H_
 #define CHROME_BROWSER_SYNC_GLUE_SYNC_BACKEND_HOST_H_
 #pragma once
 
 #include <map>
 #include <string>
@@ skipping 244 matching lines @@
                public sync_api::SyncManager::Observer {
    public:
     Core(const std::string& name, SyncBackendHost* backend);
 
     // SyncManager::Observer implementation.  The Core just acts like an air
     // traffic controller here, forwarding incoming messages to appropriate
     // landing threads.
     virtual void OnChangesApplied(
         syncable::ModelType model_type,
         const sync_api::BaseTransaction* trans,
-        const sync_api::SyncManager::ChangeRecord* changes,
-        int change_count) OVERRIDE;
+        const sync_api::ImmutableChangeRecordList& changes) OVERRIDE;
     virtual void OnChangesComplete(
         syncable::ModelType model_type) OVERRIDE;
     virtual void OnSyncCycleCompleted(
         const sessions::SyncSessionSnapshot* snapshot) OVERRIDE;
     virtual void OnInitializationComplete(
         const WeakHandle<JsBackend>& js_backend,
         bool success) OVERRIDE;
     virtual void OnAuthError(
         const GoogleServiceAuthError& auth_error) OVERRIDE;
     virtual void OnPassphraseRequired(
@@ skipping 270 matching lines @@
 
   // UI-thread cache of the last SyncSessionSnapshot received from syncapi.
   scoped_ptr<sessions::SyncSessionSnapshot> last_snapshot_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncBackendHost);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_GLUE_SYNC_BACKEND_HOST_H_