Ignore duplicated event CompleteLogin from UI

chrome/browser/chromeos/login/existing_user_controller.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/chromeos/login/existing_user_controller.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 287 matching lines @@
 string16 ExistingUserController::GetConnectedNetworkName() {
   return GetCurrentNetworkName(CrosLibrary::Get()->GetNetworkLibrary());
 }
 
 void ExistingUserController::SetDisplayEmail(const std::string& email) {
   display_email_ = email;
 }
 
 void ExistingUserController::CompleteLogin(const std::string& username,
                                            const std::string& password) {
+  if (!host_) {
+    // Complete login event was generated already from UI. Ignore notification.
+    return;
+  }
   if (!time_init_.is_null()) {
     base::TimeDelta delta = base::Time::Now() - time_init_;
     UMA_HISTOGRAM_MEDIUM_TIMES("Login.PromptToCompleteLoginTime", delta);
     time_init_ = base::Time();  // Reset to null.
   }
   host_->OnCompleteLogin();
   // Auto-enrollment must have made a decision by now. It's too late to enroll
   // if the protocol isn't done at this point.
   if (do_auto_enrollment_) {
     VLOG(1) << "Forcing auto-enrollment before completing login";
@@ skipping 602 matching lines @@
   // Invalidate OAuth token, since it can't be correct after password is
   // changed.
   UserManager::Get()->SaveUserOAuthStatus(username,
                                           User::OAUTH_TOKEN_STATUS_INVALID);
 
   login_display_->SetUIEnabled(true);
   login_display_->ShowGaiaPasswordChanged(username);
 }
 
 }  // namespace chromeos