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

components/signin/core/browser/fake_auth_status_provider.cc

Index: components/signin/core/browser/fake_auth_status_provider.cc
diff --git a/components/signin/core/browser/fake_auth_status_provider.cc b/components/signin/core/browser/fake_auth_status_provider.cc
index 8da1ef4f12ffadbe718060dd01fcccdc8a6fd0c1..77e10db9d92a691b11a5be45b5771a5f5f43bb20 100644
--- a/components/signin/core/browser/fake_auth_status_provider.cc
+++ b/components/signin/core/browser/fake_auth_status_provider.cc
@@ -18,19 +18,13 @@ std::string FakeAuthStatusProvider::GetAccountId() const {
   return account_id_;
 }
 
-std::string FakeAuthStatusProvider::GetUsername() const {
-  return username_;
-}
-
 GoogleServiceAuthError FakeAuthStatusProvider::GetAuthStatus() const {
   return auth_error_;
 }
 
 void FakeAuthStatusProvider::SetAuthError(const std::string& account_id,
-                                          const std::string& username,
                                           const GoogleServiceAuthError& error) {
   account_id_ = account_id;
-  username_ = username;
   auth_error_ = error;
   error_provider_->AuthStatusChanged();
 }