Hook up ProximityAuthSystem in EasyUnlockService.

components/proximity_auth/cryptauth/cryptauth_device_manager.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_PROXIMITY_AUTH_CRYPTAUTH_CRYPTAUTH_DEVICE_MANAGER_H
 #define COMPONENTS_PROXIMITY_AUTH_CRYPTAUTH_CRYPTAUTH_DEVICE_MANAGER_H
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
@@ skipping 26 matching lines @@
   // Represents whether the list of unlock keys has changed after a sync
   // attempt completes.
   enum class DeviceChangeResult {
     UNCHANGED,
     CHANGED,
   };
 
   class Observer {
    public:
     // Called when a sync attempt is started.
-    virtual void OnSyncStarted() = 0;
+    virtual void OnSyncStarted() {}
 
     // Called when a sync attempt finishes with the |success| of the request.
     // |devices_changed| specifies if the sync caused the stored unlock keys to
     // change.
     virtual void OnSyncFinished(SyncResult sync_result,
-                                DeviceChangeResult device_change_result) = 0;
+                                DeviceChangeResult device_change_result) {}
 
     virtual ~Observer() {}
   };
 
   // Creates the manager:
   // |clock|: Used to determine the time between sync attempts.
   // |client_factory|: Creates CryptAuthClient instances to perform each sync.
   // |gcm_manager|: Notifies when GCM push messages trigger device syncs.
   //                Not owned and must outlive this instance.
   // |pref_service|: Stores syncing metadata and unlock key information to
@@ skipping 96 matching lines @@
   base::ObserverList<Observer> observers_;
 
   base::WeakPtrFactory<CryptAuthDeviceManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CryptAuthDeviceManager);
 };
 
 }  // namespace proximity_auth
 
 #endif  // COMPONENTS_PROXIMITY_CRYPTAUTH_CRYPTAUTH_DEVICE_MANAGER_H