cros: Clear out LoginDisplayHostImpl::login_view_ before login_window_.

chrome/browser/chromeos/login/ui/login_display_host_impl.cc

 // Copyright 2014 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/ui/login_display_host_impl.h"
 
 #include <utility>
 #include <vector>
 
 #include "ash/common/wallpaper/wallpaper_controller.h"
@@ skipping 248 matching lines @@
 namespace chromeos {
 
 // static
 const int LoginDisplayHostImpl::kShowLoginWebUIid = 0x1111;
 
 ////////////////////////////////////////////////////////////////////////////////
 // LoginDisplayHostImpl, public
 
 LoginDisplayHostImpl::LoginDisplayHostImpl(const gfx::Rect& wallpaper_bounds)
     : wallpaper_bounds_(wallpaper_bounds),
-      shutting_down_(false),
-      oobe_progress_bar_visible_(false),
-      session_starting_(false),
-      login_window_(NULL),
-      login_view_(NULL),
-      webui_login_display_(NULL),
-      is_showing_login_(false),
-      is_wallpaper_loaded_(false),
-      status_area_saved_visibility_(false),
-      crash_count_(0),
-      restore_path_(RESTORE_UNKNOWN),
-      finalize_animation_type_(ANIMATION_WORKSPACE),
-      startup_sound_played_(false),
-      startup_sound_honors_spoken_feedback_(false),
-      is_observing_keyboard_(false),
       pointer_factory_(this),
       animation_weak_ptr_factory_(this) {
   if (chrome::IsRunningInMash()) {
     // Animation, and initializing hidden, are not currently supported for Mash.
     finalize_animation_type_ = ANIMATION_NONE;
     initialize_webui_hidden_ = false;
   }
 
   DBusThreadManager::Get()->GetSessionManagerClient()->AddObserver(this);
   CrasAudioHandler::Get()->AddAudioObserver(this);
@@ skipping 157 matching lines @@
 // LoginDisplayHostImpl, LoginDisplayHost:
 
 LoginDisplay* LoginDisplayHostImpl::CreateLoginDisplay(
     LoginDisplay::Delegate* delegate) {
   webui_login_display_ = new WebUILoginDisplay(delegate);
   webui_login_display_->set_background_bounds(wallpaper_bounds());
   return webui_login_display_;
 }
 
 gfx::NativeWindow LoginDisplayHostImpl::GetNativeWindow() const {
-  return login_window_ ? login_window_->GetNativeWindow() : NULL;
+  return login_window_ ? login_window_->GetNativeWindow() : nullptr;
 }
 
 WebUILoginView* LoginDisplayHostImpl::GetWebUILoginView() const {
   return login_view_;
 }
 
 void LoginDisplayHostImpl::BeforeSessionStart() {
   session_starting_ = true;
 }
 
@@ skipping 106 matching lines @@
 
   restore_path_ = RESTORE_ADD_USER_INTO_SESSION;
   completion_callback_ = completion_callback;
   // Animation is not supported in Mash
   if (!chrome::IsRunningInMash())
     finalize_animation_type_ = ANIMATION_ADD_USER;
   // Observe the user switch animation and defer the deletion of itself only
   // after the animation is finished.
   chrome::MultiUserWindowManager* window_manager =
       chrome::MultiUserWindowManager::GetInstance();
-  // MultiUserWindowManager instance might be null in a unit test.
+  // MultiUserWindowManager instance might be nullptr in a unit test.
   if (window_manager)
     window_manager->AddObserver(this);
 
   VLOG(1) << "Login WebUI >> user adding";
   if (!login_window_)
     LoadURL(GURL(kUserAddingURL));
   // We should emit this signal only at login screen (after reboot or sign out).
   login_view_->set_should_emit_login_prompt_visible(false);
 
   if (!chrome::IsRunningInMash()) {
@@ skipping 374 matching lines @@
                                                        size.height());
   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // LoginDisplayHostImpl, views::WidgetRemovalsObserver:
 void LoginDisplayHostImpl::OnWillRemoveView(views::Widget* widget,
                                             views::View* view) {
   if (view != static_cast<views::View*>(login_view_))
     return;
-  login_view_ = NULL;
+  login_view_ = nullptr;
   widget->RemoveRemovalsObserver(this);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // LoginDisplayHostImpl, chrome::MultiUserWindowManager::Observer:
 void LoginDisplayHostImpl::OnUserSwitchAnimationFinished() {
   ShutdownDisplayHost(false);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ skipping 172 matching lines @@
     VLOG(1) << "Login WebUI >> show login wnd on create";
     login_window_->Show();
   } else {
     VLOG(1) << "Login WebUI >> login wnd is hidden on create";
     login_view_->set_is_hidden(true);
   }
   login_window_->GetNativeView()->SetName("WebUILoginView");
 }
 
 void LoginDisplayHostImpl::ResetLoginWindowAndView() {
+  if (!login_view_)

[achuithb, 2017/02/06 22:38:58]

Please add a comment explaining why this order is important.

Are these early returns appropriate? Should this be:

if (login_view_) {
  login_view_->SetUIEnabled(true);
  login_view_ = nullptr;
}
if (login_window_) {
  login_window_->Close();
  login_window_ = nullptr;
}

[jdufault, 2017/02/06 22:52:10]

Done.

+    return;
+  login_view_->SetUIEnabled(true);
+  login_view_ = nullptr;
+
   if (!login_window_)
     return;
   login_window_->Close();
-  login_window_ = NULL;
-
-  if (!login_view_)
-    return;
-  login_view_->SetUIEnabled(true);
-  login_view_ = NULL;
+  login_window_ = nullptr;
 }
 
 void LoginDisplayHostImpl::OnAuthPrewarmDone() {
   auth_prewarmer_.reset();
 }
 
 void LoginDisplayHostImpl::SetOobeProgressBarVisible(bool visible) {
   GetOobeUI()->ShowOobeUI(visible);
 }
 
@@ skipping 174 matching lines @@
 
   locale_util::SwitchLanguageCallback callback(
       base::Bind(&OnLanguageSwitchedCallback, base::Passed(std::move(data))));
 
   // Load locale keyboards here. Hardware layout would be automatically enabled.
   locale_util::SwitchLanguage(locale, true, true /* login_layouts_only */,
                               callback, ProfileManager::GetActiveUserProfile());
 }
 
 }  // namespace chromeos