Cancel drag if display configuration changes.

ash/root_window_controller.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/root_window_controller.h"
 
 #include <vector>
 
 #include "ash/desktop_background/desktop_background_widget_controller.h"
 #include "ash/display/display_controller.h"
+#include "ash/display/multi_display_manager.h"
 #include "ash/shell.h"
 #include "ash/shell_factory.h"
 #include "ash/shell_window_ids.h"
 #include "ash/wm/base_layout_manager.h"
 #include "ash/wm/event_client_impl.h"
 #include "ash/wm/property_util.h"
 #include "ash/wm/root_window_layout_manager.h"
 #include "ash/wm/screen_dimmer.h"
 #include "ash/wm/system_modal_container_layout_manager.h"
 #include "ash/wm/toplevel_window_event_handler.h"
@@ skipping 267 matching lines @@
 
 RootWindowController::RootWindowController(aura::RootWindow* root_window)
     : root_window_(root_window) {
   SetRootWindowController(root_window, this);
 
   event_client_.reset(new internal::EventClientImpl(root_window));
   screen_dimmer_.reset(new internal::ScreenDimmer(root_window));
 }
 
 RootWindowController::~RootWindowController() {
+  Shutdown();
+  root_window_.reset();
+}
+
+void RootWindowController::Shutdown() {
+  CloseChildWindows();
   if (Shell::GetActiveRootWindow() == root_window_.get()) {
     Shell::GetInstance()->set_active_root_window(
         Shell::GetPrimaryRootWindow() == root_window_.get() ?
         NULL : Shell::GetPrimaryRootWindow());
   }
   SetRootWindowController(root_window_.get(), NULL);
   event_client_.reset();
   screen_dimmer_.reset();
   workspace_controller_.reset();
-  root_window_.reset();
+  // Forget with the display ID so that display lookup
+  // ends up with invalid display.
+  root_window_->ClearProperty(kDisplayIdKey);
+  // And this root window should no longer process events.
+  root_window_->PrepareForShutdown();
 }
 
 aura::Window* RootWindowController::GetContainer(int container_id) {
   return root_window_->GetChildById(container_id);
 }
 
 void RootWindowController::InitLayoutManagers() {
   root_window_layout_ =
       new internal::RootWindowLayoutManager(root_window_.get());
   root_window_->SetLayoutManager(root_window_layout_);
@@ skipping 56 matching lines @@
   // Restore focused or active window if it's still alive.
   if (focused && tracker.Contains(focused) && dst->Contains(focused)) {
     dst->GetFocusManager()->SetFocusedWindow(focused, NULL);
   } else if (active && tracker.Contains(active) && dst->Contains(active)) {
     activation_client->ActivateWindow(active);
   }
 }
 
 }  // namespace internal
 }  // namespace ash