[sync] Componentize sync: Part 2: Add SYNC_EXPORTs to files in src/sync/

sync/notifier/invalidator_state.h

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 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 SYNC_NOTIFIER_INVALIDATOR_STATE_H_
 #define SYNC_NOTIFIER_INVALIDATOR_STATE_H_
 
 #include "jingle/notifier/listener/push_client_observer.h"
+#include "sync/base/sync_export.h"
 
 namespace syncer {
 
 enum InvalidatorState {
   // Failure states
   // --------------
   // There is an underlying transient problem (e.g., network- or
   // XMPP-related).
   TRANSIENT_INVALIDATION_ERROR,
   DEFAULT_INVALIDATION_ERROR = TRANSIENT_INVALIDATION_ERROR,
   // Our credentials have been rejected.
   INVALIDATION_CREDENTIALS_REJECTED,
 
   // Invalidations are fully working.
   INVALIDATIONS_ENABLED
 };
 
-const char* InvalidatorStateToString(InvalidatorState state);
+SYNC_EXPORT const char* InvalidatorStateToString(InvalidatorState state);
 
 InvalidatorState FromNotifierReason(
     notifier::NotificationsDisabledReason reason);
 
 // Should not be called when |state| == INVALIDATIONS_ENABLED.
 notifier::NotificationsDisabledReason ToNotifierReasonForTest(
     InvalidatorState state);
 
 }  // namespace syncer
 
 #endif  // SYNC_NOTIFIER_INVALIDATOR_STATE_H_