Delete blimp/helium and remove references to it from dependent targets

blimp/helium/sync_manager.h

-// Copyright 2016 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 BLIMP_HELIUM_SYNC_MANAGER_H_
-#define BLIMP_HELIUM_SYNC_MANAGER_H_
-
-#include <stdint.h>
-#include <memory>
-
-#include "base/macros.h"
-
-namespace blimp {
-namespace helium {
-
-class HeliumObject;
-class HeliumTransport;
-class Syncable;
-
-using HeliumObjectId = uint32_t;
-
-// TODO(kmarshall): Define this type.
-class HeliumTransport {};
-
-class SyncManager {
- public:
-  // RAII object for managing the sync control and registration status of a
-  // Syncable. When a Syncable is registered, it should hold onto the resulting
-  // SyncRegistration object.
-  //
-  // When the Syncable is destroyed, it will delete the
-  // SyncRegistration along with it, which will automatically unregister the
-  // object from the SyncManager.
-  //
-  // If a Syncable wishes to halt synchronization for any reason (e.g. a tab
-  // is hidden on the Client), it may call SyncRegistration::Pause(), which will
-  // tell the SyncManager to exclude or include the Syncable in state sync.
-  class SyncRegistration {
-   public:
-    SyncRegistration(SyncManager* sync_manager, HeliumObjectId id);
-    ~SyncRegistration();
-
-    // Tells the HeliumSyncManager to pause or unpause synchronization for the
-    // HeliumObject associated with |this|.
-    void Pause(bool paused);
-
-    HeliumObjectId id() { return id_; }
-
-   private:
-    HeliumObjectId id_;
-    SyncManager* sync_manager_;
-
-    DISALLOW_COPY_AND_ASSIGN(SyncRegistration);
-  };
-
-  virtual ~SyncManager() {}
-
-  // Returns a concrete implementation of HeliumSyncManager.
-  static std::unique_ptr<SyncManager> Create(
-      std::unique_ptr<HeliumTransport> transport);
-
-  // Registers a new Syncable for synchronization. The Sync layer allocates a
-  // unique identifier to the Object (including guaranteeing no clashes between
-  // Client & Engine).
-  // The identifier may be used by other Objects to refer to |object|. E.g. the
-  // tab-list Object might include the Id for each tab’s Object.
-  virtual std::unique_ptr<SyncRegistration> Register(Syncable* syncable) = 0;
-
-  // Registers a Syncable for synchronization with a pre-existing ID.
-  // This form is used when the remote peer has created a new Syncable, to
-  // register our local equivalent.
-  virtual std::unique_ptr<SyncRegistration> RegisterExisting(
-      HeliumObjectId id,
-      Syncable* syncable) = 0;
-
- protected:
-  friend class SyncManager::SyncRegistration;
-
-  // Tells the HeliumSyncManager to pause or unpause synchronization for the
-  // HeliumObject associated with |this|.
-  virtual void Pause(HeliumObjectId id, bool paused) = 0;
-
-  // Indicates that a Syncable is being destroyed, and should no longer be
-  // synchronized.
-  // Because the Syncable is being destroyed, it is assumed that in-flight
-  // messages
-  // about it are now irrelevant, and the Sync layer should tear down underlying
-  // resources, such as the HeliumStream, immediately.
-  virtual void Unregister(HeliumObjectId id) = 0;
-};
-
-}  // namespace helium
-}  // namespace blimp
-
-#endif  // BLIMP_HELIUM_SYNC_MANAGER_H_