[CrOS Tether] Update TetherHostFetcher to use CryptAuthService instead of a Delegate.

chromeos/components/tether/tether_host_fetcher.h

 // Copyright 2017 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 CHROMEOS_COMPONENTS_TETHER_TETHER_HOST_FETCHER_H_
 #define CHROMEOS_COMPONENTS_TETHER_TETHER_HOST_FETCHER_H_
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "components/cryptauth/remote_device.h"
 
 namespace cryptauth {
 class CryptAuthDeviceManager;
+class CryptAuthService;
 class RemoteDeviceLoader;
-class SecureMessageDelegate;
 }  // namespace cryptauth
 
 namespace chromeos {
 
 namespace tether {
 
 // Fetches RemoteDevice objects corresponding to tether hosts which have been
 // synced via CryptAuth.
 class TetherHostFetcher {
  public:
-  class Delegate {
-   public:
-    virtual std::unique_ptr<cryptauth::SecureMessageDelegate>
-    CreateSecureMessageDelegate() = 0;
-  };
-
   TetherHostFetcher(const std::string& user_id,
                     const std::string& user_private_key,
-                    std::unique_ptr<Delegate> delegate,
+                    cryptauth::CryptAuthService* cryptauth_service,
                     cryptauth::CryptAuthDeviceManager* device_manager);
   virtual ~TetherHostFetcher();
 
   // Fetches all tether hosts.
   using TetherHostListCallback =
       base::Callback<void(const cryptauth::RemoteDeviceList&)>;
   virtual void FetchAllTetherHosts(const TetherHostListCallback& callback);
 
   // Fetches the tether host with the ID |device_id|.
   using TetherHostCallback =
@@ skipping 21 matching lines @@
 
   void OnRemoteDevicesLoaded(const cryptauth::RemoteDeviceList& remote_devices);
 
   std::vector<TetherHostFetchRequest> requests_;
 
  private:
   void StartLoadingDevicesIfNeeded();
 
   const std::string user_id_;
   const std::string user_private_key_;
-  std::unique_ptr<Delegate> delegate_;
+
+  cryptauth::CryptAuthService* cryptauth_service_;
   cryptauth::CryptAuthDeviceManager* device_manager_;
 
   std::unique_ptr<cryptauth::RemoteDeviceLoader> remote_device_loader_;
 
   base::WeakPtrFactory<TetherHostFetcher> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TetherHostFetcher);
 };
 
 }  // namespace tether
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_COMPONENTS_TETHER_TETHER_HOST_FETCHER_H_