Added login screen mode for adding users into session.

chrome/browser/chromeos/login/user_adding_screen.cc

Index: chrome/browser/chromeos/login/user_adding_screen.cc
diff --git a/chrome/browser/chromeos/login/user_adding_screen.cc b/chrome/browser/chromeos/login/user_adding_screen.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c611d6d3fa8c1e083adc040edff759fe5c770d39
--- /dev/null
+++ b/chrome/browser/chromeos/login/user_adding_screen.cc
@@ -0,0 +1,96 @@
+// Copyright (c) 2013 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/user_adding_screen.h"
+
+#include "base/bind.h"
+#include "base/memory/singleton.h"
+#include "base/observer_list.h"
+#include "chrome/browser/chromeos/login/helper.h"
+#include "chrome/browser/chromeos/login/login_display_host_impl.h"
+#include "ui/gfx/rect.h"
+#include "ui/gfx/size.h"
+
+namespace chromeos {
+
+namespace {
+
+class UserAddingScreenImpl : public UserAddingScreen {
+ public:
+  virtual void Start() OVERRIDE;
+  virtual void Cancel() OVERRIDE;
+  virtual bool IsRunning() OVERRIDE;
+
+  virtual void AddObserver(Observer* observer) OVERRIDE;
+  virtual void RemoveObserver(Observer* observer) OVERRIDE;
+
+  static UserAddingScreenImpl* GetInstance();
+ private:
+  friend struct DefaultSingletonTraits<UserAddingScreenImpl>;
+
+  void OnDisplayHostCompletion();
+
+  UserAddingScreenImpl();
+  virtual ~UserAddingScreenImpl();
+
+  ObserverList<Observer> observers_;
+  LoginDisplayHost* display_host_;
+};
+
+void UserAddingScreenImpl::Start() {
+  CHECK(!IsRunning());
+  gfx::Rect screen_bounds(chromeos::CalculateScreenBounds(gfx::Size()));
+  display_host_ = new chromeos::LoginDisplayHostImpl(screen_bounds);
+  display_host_->StartUserAdding(
+      base::Bind(&UserAddingScreenImpl::OnDisplayHostCompletion,
+                 base::Unretained(this)));
+  FOR_EACH_OBSERVER(Observer, observers_, OnUserAddingStarted());
+}
+
+void UserAddingScreenImpl::Cancel() {
+  CHECK(IsRunning());
+  display_host_->Finalize();
+}
+
+bool UserAddingScreenImpl::IsRunning() {
+  return display_host_ != NULL;
+}
+
+void UserAddingScreenImpl::AddObserver(Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void UserAddingScreenImpl::RemoveObserver(Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+void UserAddingScreenImpl::OnDisplayHostCompletion() {
+  CHECK(IsRunning());
+  display_host_ = NULL;
+  FOR_EACH_OBSERVER(Observer, observers_, OnUserAddingFinished());
+}
+
+// static
+UserAddingScreenImpl* UserAddingScreenImpl::GetInstance() {
+  return Singleton<UserAddingScreenImpl>::get();
+}
+
+UserAddingScreenImpl::UserAddingScreenImpl()
+  : display_host_(NULL) {
+}
+
+UserAddingScreenImpl::~UserAddingScreenImpl() {
+}
+
+}  // anonymous namespace
+
+UserAddingScreen::UserAddingScreen() {}
+UserAddingScreen::~UserAddingScreen() {}
+
+UserAddingScreen* UserAddingScreen::Get() {
+  return UserAddingScreenImpl::GetInstance();
+}
+
+}  // namespace chromeos
+