[ARC] Add browser test of ArcAuthService

chrome/browser/chromeos/arc/arc_auth_service.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 CHROME_BROWSER_CHROMEOS_ARC_ARC_AUTH_SERVICE_H_
 #define CHROME_BROWSER_CHROMEOS_ARC_ARC_AUTH_SERVICE_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 11 matching lines @@
 
 // Implementation of ARC authorization.
 // TODO(hidehiko): Move to c/b/c/arc/auth with adding tests.
 class ArcAuthService : public ArcService,
                        public mojom::AuthHost,
                        public InstanceHolder<mojom::AuthInstance>::Observer {
  public:
   explicit ArcAuthService(ArcBridgeService* bridge_service);
   ~ArcAuthService() override;
 
-  // This is introduced to work with existing tests.
-  // TODO(crbug.com/664095): Clean up the test and remove this method.
-  static ArcAuthService* GetForTest();
+  // For supporting ArcServiceManager::GetService<T>().
+  static const char kArcServiceName[];
 
   // InstanceHolder<mojom::AuthInstance>::Observer:
   void OnInstanceReady() override;
   void OnInstanceClosed() override;
 
   // mojom::AuthHost:
   void OnSignInComplete() override;
   void OnSignInFailed(mojom::ArcSignInFailureReason reason) override;
   void RequestAccountInfo() override;
   void ReportMetrics(mojom::MetricsType metrics_type, int32_t value) override;
@@ skipping 35 matching lines @@
   std::unique_ptr<ArcFetcherBase> fetcher_;
 
   base::WeakPtrFactory<ArcAuthService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcAuthService);
 };
 
 }  // namespace arc
 
 #endif  // CHROME_BROWSER_CHROMEOS_ARC_ARC_AUTH_SERVICE_H_