Focus kept on login screen.

ash/wm/event_client_impl.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 "ash/wm/event_client_impl.h"
 
 #include "ash/session_state_delegate.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ui/aura/window.h"
 
 namespace ash {
 namespace internal {
 
 EventClientImpl::EventClientImpl() {
 }
 
 EventClientImpl::~EventClientImpl() {
 }
 
 bool EventClientImpl::CanProcessEventsWithinSubtree(
     const aura::Window* window) const {
-  const aura::RootWindow* root_window =
-      window ? window->GetRootWindow() : NULL;
-  if (Shell::GetInstance()->session_state_delegate()->IsScreenLocked() &&
-      root_window) {
+  const aura::RootWindow* root_window = window ? window->GetRootWindow() : NULL;
+  if (!root_window)
+    return true;
+  ash::SessionStateDelegate* state_delegate =
+      Shell::GetInstance()->session_state_delegate();
+  if (!state_delegate->IsActiveUserSessionStarted() ||
+      state_delegate->IsScreenLocked()) {
     const aura::Window* lock_screen_containers = Shell::GetContainer(
         root_window,
         kShellWindowId_LockScreenContainersContainer);
     const aura::Window* lock_background_containers = Shell::GetContainer(
         root_window,
         kShellWindowId_LockScreenBackgroundContainer);
     const aura::Window* lock_screen_related_containers = Shell::GetContainer(
         root_window,
         kShellWindowId_LockScreenRelatedContainersContainer);
     return (window->Contains(lock_screen_containers) &&
         window->Contains(lock_background_containers) &&
         window->Contains(lock_screen_related_containers)) ||
         lock_screen_containers->Contains(window) ||
         lock_background_containers->Contains(window) ||
         lock_screen_related_containers->Contains(window);
   }
   return true;
 }
 
 ui::EventTarget* EventClientImpl::GetToplevelEventTarget() {
   return Shell::GetInstance();
 }
 
 }  // namespace internal
 }  // namespace ash