Switching to the correct desktop when a system modal dialog gets shown

chrome/browser/ui/ash/multi_user/multi_user_window_manager_chromeos.cc

 // Copyright 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/ui/ash/multi_user/multi_user_window_manager_chromeos.h"
 
 #include "apps/shell_window.h"
 #include "apps/shell_window_registry.h"
 #include "ash/ash_switches.h"
 #include "ash/multi_profile_uma.h"
 #include "ash/session_state_delegate.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
+#include "ash/shell_window_ids.h"
 #include "ash/wm/mru_window_tracker.h"
 #include "ash/wm/window_positioner.h"
 #include "ash/wm/window_state.h"
 #include "base/auto_reset.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 436 matching lines @@
     return;
   SetWindowOwner(browser->window()->GetNativeWindow(),
                  multi_user_util::GetUserIDFromProfile(browser->profile()));
 }
 
 void MultiUserWindowManagerChromeOS::SetWindowVisibility(
     aura::Window* window, bool visible) {
   if (window->IsVisible() == visible)
     return;
 
+  // Hiding a system modal dialog should not be allowed. Instead we switch to
+  // the user which is showing the system modal window.
+  // Note that in some cases (e.g. unit test) windows might not have a root
+  // window.
+  if (!visible && window->GetRootWindow()) {
+    // Get the system modal container for the window's root window.
+    aura::Window* system_modal_container =
+        window->GetRootWindow()->GetChildById(
+            ash::internal::kShellWindowId_SystemModalContainer);
+    if (window->parent() == system_modal_container) {
+      // The window is system modal and we need to find the parent which owns
+      // it so that we can switch to the desktop accordingly.
+      std::string user_id = GetUserPresentingWindow(window);
+      if (user_id.empty()) {
+        aura::Window* owning_window = GetOwningWindowInTransientChain(window);
+        DCHECK(owning_window);
+        user_id = GetUserPresentingWindow(owning_window);
+        DCHECK(!user_id.empty());
+      }
+      ash::Shell::GetInstance()->session_state_delegate()->SwitchActiveUser(
+          user_id);
+      return;
+    }
+  }
+
   // To avoid that these commands are recorded as any other commands, we are
   // suppressing any window entry changes while this is going on.
   base::AutoReset<bool> suppressor(&suppress_visibility_changes_, true);
 
   if (visible) {
     ShowWithTransientChildrenRecursive(window);
   } else {
     if (window->HasFocus())
       window->Blur();
     window->Hide();
@@ skipping 78 matching lines @@
     // To prevent these commands from being recorded as any other commands, we
     // are suppressing any window entry changes while this is going on.
     // Instead of calling SetWindowVisible, only show gets called here since all
     // dependents have been shown previously already.
     base::AutoReset<bool> suppressor(&suppress_visibility_changes_, true);
     window->Show();
   }
 }
 
 }  // namespace chrome