Add a mojo interface for AccountId

ash/common/session/session_controller.cc

 // 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.
 
 #include "ash/common/session/session_controller.h"
 
 #include <algorithm>
 
 #include "ash/common/session/session_state_observer.h"
 #include "base/bind.h"
@@ skipping 52 matching lines @@
   return user_sessions_;
 }
 
 void SessionController::LockScreen() {
   if (client_)
     client_->RequestLockScreen();
 }
 
 void SessionController::SwitchActiveUser(const AccountId& account_id) {
   if (client_)
-    client_->SwitchActiveUser(account_id.Serialize());
+    client_->SwitchActiveUser(account_id);
 }
 
 void SessionController::CycleActiveUser(bool next_user) {
   if (client_)
     client_->CycleActiveUser(next_user);
 }
 
 void SessionController::AddSessionStateObserver(
     SessionStateObserver* observer) {
   observers_.AddObserver(observer);
@@ skipping 50 matching lines @@
     }
 
     sessions.push_back(std::move(*it));
   }
   user_sessions_.swap(sessions);
 
   // Check active user change and notifies observers.
   if (user_sessions_[0]->session_id != active_session_id_) {
     active_session_id_ = user_sessions_[0]->session_id;
 
-    AccountId account_id(EmptyAccountId());
-    if (AccountId::Deserialize(user_sessions_[0]->serialized_account_id,
-                               &account_id)) {
-      for (auto& observer : observers_)
-        observer.ActiveUserChanged(account_id);
-    }
+    for (auto& observer : observers_)
+      observer.ActiveUserChanged(user_sessions_[0]->account_id);
   }
 }
 
 void SessionController::SetSessionState(session_manager::SessionState state) {
   if (state_ == state)
     return;
 
   state_ = state;
   for (auto& observer : observers_)
     observer.SessionStateChanged(state_);
 }
 
 void SessionController::AddUserSession(mojom::UserSessionPtr user_session) {
-  AccountId account_id(EmptyAccountId());
-  if (!AccountId::Deserialize(user_session->serialized_account_id,
-                              &account_id)) {
-    LOG(ERROR) << "Failed to deserialize account id.";
-    return;
-  }
+  const AccountId account_id(user_session->account_id);
 
   user_sessions_.push_back(std::move(user_session));
 
   for (auto& observer : observers_)
     observer.UserAddedToSession(account_id);
 }
 
 }  // namespace ash