arc: Restore UMA statistics for failures in LSO flow.

chrome/browser/chromeos/arc/auth/arc_manual_auth_code_fetcher.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_AUTH_ARC_MANUAL_AUTH_CODE_FETCHER_H_
 #define CHROME_BROWSER_CHROMEOS_ARC_AUTH_ARC_MANUAL_AUTH_CODE_FETCHER_H_
 
 #include <string>
 
 #include "base/macros.h"
@@ skipping 22 matching lines @@
   void Fetch(const FetchCallback& callback) override;
 
  private:
   void FetchInternal();
 
   // Called when HTTP request gets ready.
   void OnContextPrepared(net::URLRequestContextGetter* request_context_getter);
 
   // ArcSupportHost::Observer:
   void OnAuthSucceeded(const std::string& auth_code) override;
+  void OnAuthFailed() override;
   void OnRetryClicked() override;
 
   ArcAuthContext* const context_;
   ArcSupportHost* const support_host_;
 
   FetchCallback pending_callback_;
 
   base::WeakPtrFactory<ArcManualAuthCodeFetcher> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcManualAuthCodeFetcher);
 };
 
 }  // namespace arc
 
 #endif  // CHROME_BROWSER_CHROMEOS_ARC_AUTH_ARC_MANUAL_AUTH_CODE_FETCHER_H_