[Sync] Fixing sync_driver lint violations and adding PRESUBMIT lint check.

components/sync_driver/sync_prefs.h

 // Copyright (c) 2012 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 COMPONENTS_SYNC_DRIVER_SYNC_PREFS_H_
 #define COMPONENTS_SYNC_DRIVER_SYNC_PREFS_H_
 
+#include <map>
+#include <string>
+
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "base/prefs/pref_member.h"
 #include "base/threading/non_thread_safe.h"
 #include "base/time/time.h"
 #include "sync/internal_api/public/base/model_type.h"
 #include "sync/internal_api/public/sync_encryption_handler.h"
 
@@ skipping 196 matching lines @@
   // etc.
   typedef std::map<syncer::ModelType, syncer::ModelTypeSet> PrefGroupsMap;
   PrefGroupsMap pref_groups_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncPrefs);
 };
 
 }  // namespace sync_driver
 
 #endif  // COMPONENTS_SYNC_DRIVER_SYNC_PREFS_H_