Profile chooser on mac was passing wrong value to signin error controller.

components/signin/core/browser/fake_auth_status_provider.h

 // Copyright 2014 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_SIGNIN_CORE_BROWSER_FAKE_AUTH_STATUS_PROVIDER_H_
 #define COMPONENTS_SIGNIN_CORE_BROWSER_FAKE_AUTH_STATUS_PROVIDER_H_
 
 #include "components/signin/core/browser/signin_error_controller.h"
 
 // Helper class that reports auth errors to SigninErrorController. Automatically
 // registers and de-registers itself as an AuthStatusProvider in the
 // constructor and destructor.
 class FakeAuthStatusProvider
     : public SigninErrorController::AuthStatusProvider {
  public:
   explicit FakeAuthStatusProvider(SigninErrorController* error);
   ~FakeAuthStatusProvider() override;
 
   // Sets the auth error that this provider reports to SigninErrorController.
   // Also notifies SigninErrorController via AuthStatusChanged().
   void SetAuthError(const std::string& account_id,
-                    const std::string& username,
                     const GoogleServiceAuthError& error);
 
   void set_error_without_status_change(const GoogleServiceAuthError& error) {
     auth_error_ = error;
   }
 
   // AuthStatusProvider implementation.
   std::string GetAccountId() const override;
-  std::string GetUsername() const override;
   GoogleServiceAuthError GetAuthStatus() const override;
 
  private:
   SigninErrorController* error_provider_;
   std::string account_id_;
-  std::string username_;
   GoogleServiceAuthError auth_error_;
 };
 
 #endif  // COMPONENTS_SIGNIN_CORE_BROWSER_FAKE_AUTH_STATUS_PROVIDER_H_