components: Cleanup class/struct fwd declarations

components/sync/engine_impl/sync_scheduler.h

 // 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 COMPONENTS_SYNC_ENGINE_IMPL_SYNC_SCHEDULER_H_
 #define COMPONENTS_SYNC_ENGINE_IMPL_SYNC_SCHEDULER_H_
 
 #include <memory>
 #include <string>
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/time/time.h"
 #include "components/sync/base/invalidation_interface.h"
 #include "components/sync/engine_impl/cycle/sync_cycle.h"
 #include "components/sync/engine_impl/nudge_source.h"
 
 namespace tracked_objects {
 class Location;
 }  // namespace tracked_objects
 
 namespace syncer {
 
-struct ServerConnectionEvent;
-
 struct ConfigurationParams {
   ConfigurationParams();
   ConfigurationParams(
       const sync_pb::GetUpdatesCallerInfo::GetUpdatesSource& source,
       ModelTypeSet types_to_download,
       const ModelSafeRoutingInfo& routing_info,
       const base::Closure& ready_task,
       const base::Closure& retry_task);
   ConfigurationParams(const ConfigurationParams& other);
   ~ConfigurationParams();
@@ skipping 113 matching lines @@
   // Called when credentials are updated by the user.
   virtual void OnCredentialsUpdated() = 0;
 
   // Called when the network layer detects a connection status change.
   virtual void OnConnectionStatusChange() = 0;
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_ENGINE_IMPL_SYNC_SCHEDULER_H_