arc: Revamp the ArcBridgeService interface

components/arc/net/arc_net_host_impl.h

 // Copyright 2015 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_ARC_NET_ARC_NET_HOST_IMPL_H_
 #define COMPONENTS_ARC_NET_ARC_NET_HOST_IMPL_H_
 
 #include <stdint.h>
 #include <string>
 #include <vector>
 
 #include "base/files/scoped_file.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread_checker.h"
 #include "chromeos/network/network_state_handler_observer.h"
 #include "components/arc/arc_bridge_service.h"
 #include "components/arc/arc_service.h"
 #include "components/arc/common/net.mojom.h"
+#include "components/arc/instance_holder.h"
 #include "mojo/public/cpp/bindings/binding.h"
 
 namespace base {
 
 class DictionaryValue;
 
 }  // namespace base
 
 namespace arc {
 
 class ArcBridgeService;
 
 // Private implementation of ArcNetHost.
 class ArcNetHostImpl : public ArcService,
-                       public ArcBridgeService::Observer,
+                       public InstanceHolder<mojom::NetInstance>::Observer,
                        public chromeos::NetworkStateHandlerObserver,
                        public mojom::NetHost {
  public:
   // The constructor will register an Observer with ArcBridgeService.
   explicit ArcNetHostImpl(ArcBridgeService* arc_bridge_service);
   ~ArcNetHostImpl() override;
 
   // ARC -> Chrome calls:
 
   void GetNetworksDeprecated(
@@ skipping 25 matching lines @@
   void StartDisconnect(const mojo::String& guid,
                        const StartDisconnectCallback& callback) override;
 
   // Overriden from chromeos::NetworkStateHandlerObserver.
   void ScanCompleted(const chromeos::DeviceState* /*unused*/) override;
   void OnShuttingDown() override;
   void DefaultNetworkChanged(const chromeos::NetworkState* network) override;
   void DeviceListChanged() override;
   void GetDefaultNetwork(const GetDefaultNetworkCallback& callback) override;
 
-  // Overridden from ArcBridgeService::Observer:
-  void OnNetInstanceReady() override;
+  // Overridden from ArcBridgeService::InterfaceObserver<mojom::NetInstance>:
+  void OnInstanceReady() override;
 
  private:
   void DefaultNetworkSuccessCallback(const std::string& service_path,
                                      const base::DictionaryValue& dictionary);
   base::ThreadChecker thread_checker_;
   mojo::Binding<arc::mojom::NetHost> binding_;
   base::WeakPtrFactory<ArcNetHostImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcNetHostImpl);
 };
 
 }  // namespace arc
 
 #endif  // COMPONENTS_ARC_NET_ARC_NET_HOST_IMPL_H_