ash: Fix event processing in modal windows in login/lock screen.

ash/shell.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/shell.h"
 
 #include <algorithm>
 #include <string>
 
 #include "ash/accelerators/focus_manager_factory.h"
@@ skipping 215 matching lines @@
   RemoveEnvEventFilter(accelerator_filter_.get());
 #endif
   if (touch_observer_hud_.get())
     RemoveEnvEventFilter(touch_observer_hud_.get());
 
   // TooltipController is deleted with the Shell so removing its references.
   RemoveEnvEventFilter(tooltip_controller_.get());
 
   // The status area needs to be shut down before the windows are destroyed.
   status_area_widget_->Shutdown();
+  status_area_widget_ = NULL;
 
   // AppList needs to be released before shelf layout manager, which is
   // destroyed with launcher container in the loop below. However, app list
   // container is now on top of launcher container and released after it.
   // TODO(xiyuan): Move it back when app list container is no longer needed.
   app_list_controller_.reset();
 
 
   // Closing the windows frees the workspace controller.
   shelf_->set_workspace_controller(NULL);
@@ skipping 418 matching lines @@
 }
 
 void Shell::CreateModalBackground() {
   if (!modality_filter_.get()) {
     modality_filter_.reset(new internal::SystemModalContainerEventFilter(this));
     AddEnvEventFilter(modality_filter_.get());
   }
   RootWindowControllerList controllers = GetAllRootWindowControllers();
   for (RootWindowControllerList::iterator iter = controllers.begin();
        iter != controllers.end(); ++iter)
-    (*iter)->GetSystemModalLayoutManager()->CreateModalBackground();
+    (*iter)->GetSystemModalLayoutManager(NULL)->CreateModalBackground();
 }
 
 void Shell::OnModalWindowRemoved(aura::Window* removed) {
   RootWindowControllerList controllers = GetAllRootWindowControllers();
   bool activated = false;
   for (RootWindowControllerList::iterator iter = controllers.begin();
        iter != controllers.end() && !activated; ++iter) {
-    activated =
-        (*iter)->GetSystemModalLayoutManager()->ActivateNextModalWindow();
+    activated = (*iter)->GetSystemModalLayoutManager(removed)->
+        ActivateNextModalWindow();
   }
   if (!activated) {
     RemoveEnvEventFilter(modality_filter_.get());
     modality_filter_.reset();
     for (RootWindowControllerList::iterator iter = controllers.begin();
          iter != controllers.end(); ++iter)
-      (*iter)->GetSystemModalLayoutManager()->DestroyModalBackground();
+      (*iter)->GetSystemModalLayoutManager(removed)->DestroyModalBackground();
   }
 }
 
 SystemTrayDelegate* Shell::tray_delegate() {
-  return status_area_widget_->system_tray_delegate();
+  return status_area_widget_ ? status_area_widget_->system_tray_delegate() :
+                               NULL;
 }
 
 SystemTray* Shell::system_tray() {
-  return status_area_widget_->system_tray();
+  return status_area_widget_ ? status_area_widget_->system_tray() :
+                               NULL;
 }
 
 void Shell::InitRootWindowForSecondaryDisplay(aura::RootWindow* root) {
   root->set_focus_manager(focus_manager_.get());
   internal::RootWindowController* controller =
       new internal::RootWindowController(root);
   controller->CreateContainers();
   InitRootWindowController(controller);
   controller->root_window_layout()->OnWindowResized();
   desktop_background_controller_->OnRootWindowAdded(root);
@@ skipping 41 matching lines @@
 
   // TODO(oshima): Move the instance to RootWindowController when
   // the extended desktop is enabled by default.
   internal::AlwaysOnTopController* always_on_top_controller =
       new internal::AlwaysOnTopController;
   always_on_top_controller->SetContainers(
       root_window->GetChildById(internal::kShellWindowId_DefaultContainer),
       root_window->GetChildById(internal::kShellWindowId_AlwaysOnTopContainer));
   root_window->SetProperty(internal::kAlwaysOnTopControllerKey,
                            always_on_top_controller);
-  if (GetPrimaryRootWindowController()->GetSystemModalLayoutManager()->
+  if (GetPrimaryRootWindowController()->GetSystemModalLayoutManager(NULL)->
           has_modal_background()) {
-    controller->GetSystemModalLayoutManager()->CreateModalBackground();
+    controller->GetSystemModalLayoutManager(NULL)->CreateModalBackground();
   }
 
   window_cycle_controller_->OnRootWindowAdded(root_window);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // Shell, private:
 
 void Shell::InitLayoutManagersForPrimaryDisplay(
     internal::RootWindowController* controller) {
@@ skipping 39 matching lines @@
   RootWindowList root_windows = GetAllRootWindows();
   for (RootWindowList::iterator iter = root_windows.begin();
        iter != root_windows.end(); ++iter)
     (*iter)->ShowCursor(visible);
 }
 
 bool Shell::CanWindowReceiveEvents(aura::Window* window) {
   RootWindowControllerList controllers = GetAllRootWindowControllers();
   for (RootWindowControllerList::iterator iter = controllers.begin();
        iter != controllers.end(); ++iter) {
-    if ((*iter)->GetSystemModalLayoutManager()->
+    if ((*iter)->GetSystemModalLayoutManager(window)->
             CanWindowReceiveEvents(window)) {
       return true;
     }
   }
   return false;
 }
 
 }  // namespace ash