Wait for Cryptohome service to be available on login.

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 <memory>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 1220 matching lines @@
     bool start_auto_login_timer) {
   is_login_in_progress_ = false;
 
   // Reenable clicking on other windows and status area.
   login_display_->SetUIEnabled(true);
 
   if (start_auto_login_timer)
     StartAutoLoginTimer();
 }
 
+void ExistingUserController::ContinueLoginWhenCryptohomeAvailable(
+    const base::Closure& continuation,
+    bool service_is_available) {
+  if (!service_is_available) {
+    login_display_->SetUIEnabled(true);

[xiyuan, 2017/04/13 18:07:31]

How about do

  LOG(ERROR) << "Cryptohome service is not available";
  OnAuthFailure(AuthFailure::COULD_NOT_MOUNT_CRYPTOHOME);

so that we get it in log and user gets some visual feedback?

[Sergey Poromov, 2017/04/18 12:50:56]

Done.

+    return;
+  }
+  continuation.Run();
+}
+
 void ExistingUserController::ContinueLoginIfDeviceNotDisabled(
     const base::Closure& continuation) {
   // Disable clicking on other windows and status tray.
   login_display_->SetUIEnabled(false);
 
   // Stop the auto-login timer.
   StopAutoLoginTimer();
 
   // Wait for the |cros_settings_| to become either trusted or permanently
   // untrusted.
@@ skipping 25 matching lines @@
                              HonorDeviceDisablingDuringNormalOperation()) {
     // If the device is disabled, bail out. A device disabled screen will be
     // shown by the DeviceDisablingManager.
 
     // Re-enable clicking on other windows and the status area. Do not start the
     // auto-login timer though. On a disabled device, no auto-login can succeed.
     login_display_->SetUIEnabled(true);
     return;
   }
 
-  continuation.Run();
+  chromeos::DBusThreadManager::Get()
+      ->GetCryptohomeClient()
+      ->WaitForServiceToBeAvailable(base::Bind(
+          &ExistingUserController::ContinueLoginWhenCryptohomeAvailable,
+          weak_factory_.GetWeakPtr(), continuation));
 }
 
 void ExistingUserController::DoCompleteLogin(
     const UserContext& user_context_wo_device_id) {
   UserContext user_context = user_context_wo_device_id;
   std::string device_id =
       user_manager::known_user::GetDeviceId(user_context.GetAccountId());
   if (device_id.empty()) {
     bool is_ephemeral = ChromeUserManager::Get()->AreEphemeralUsersEnabled() &&
                         user_context.GetAccountId() !=
@@ skipping 138 matching lines @@
   login_display_->ShowUnrecoverableCrypthomeErrorDialog();
 }
 
 void ExistingUserController::ClearRecordedNames() {
   display_email_.clear();
   display_name_.clear();
   given_name_.clear();
 }
 
 }  // namespace chromeos