components: Cleanup class/struct fwd declarations

components/sync/engine_impl/all_status.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_ENGINE_IMPL_ALL_STATUS_H_
 #define COMPONENTS_SYNC_ENGINE_IMPL_ALL_STATUS_H_
 
 #include <map>
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/synchronization/lock.h"
 #include "components/sync/base/model_type.h"
 #include "components/sync/engine/sync_status.h"
 #include "components/sync/engine_impl/nudge_source.h"
 #include "components/sync/engine_impl/sync_engine_event_listener.h"
 #include "components/sync/engine_impl/syncer_types.h"
 
 namespace syncer {
 
 class ScopedStatusLock;
-struct ServerConnectionEvent;
 struct SyncCycleEvent;
 
 // This class watches various sync engine components, updating its internal
 // state upon change. It can return a snapshot of this state as a SyncerStatus
 // object, aggregating all this data into one place.
 //
 // Most of this data ends up on the about:sync page.  But the page is only
 // 'pinged' to update itself at the end of a sync cycle.  A user could refresh
 // manually, but unless their timing is excellent it's unlikely that a user will
 // see any state in mid-sync cycle.  We have no plans to change this.  However,
@@ skipping 54 matching lines @@
   explicit ScopedStatusLock(AllStatus* allstatus);
   ~ScopedStatusLock();
 
  protected:
   AllStatus* allstatus_;
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_ENGINE_IMPL_ALL_STATUS_H_