Cancel drag upon screen lock

ash/drag_drop/drag_drop_tracker.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/drag_drop/drag_drop_tracker.h"
 
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/wm/coordinate_conversion.h"
 #include "ui/aura/root_window.h"
 #include "ui/base/events/event.h"
 #include "ui/gfx/screen.h"
 
+namespace ash {
+namespace internal {
+
 namespace {
 
 // Creates a window for capturing drag events.
-aura::Window* CreateCaptureWindow(aura::RootWindow* context_root) {
-  aura::Window* window = new aura::Window(NULL);
+aura::Window* CreateCaptureWindow(aura::RootWindow* context_root,
+                                  aura::WindowDelegate* delegate) {
+  aura::Window* window = new aura::Window(delegate);
   window->SetType(aura::client::WINDOW_TYPE_NORMAL);
   window->Init(ui::LAYER_NOT_DRAWN);
   window->SetDefaultParentByRootWindow(context_root, gfx::Rect());
   window->Show();
+  DCHECK(window->bounds().size().IsEmpty());
   return window;
 }
 
 }  // namespace
 
-namespace ash {
-namespace internal {
-
-DragDropTracker::DragDropTracker(aura::RootWindow* context_root)
-    : capture_window_(CreateCaptureWindow(context_root)) {
+DragDropTracker::DragDropTracker(aura::RootWindow* context_root,
+                                 aura::WindowDelegate* delegate)
+    : capture_window_(CreateCaptureWindow(context_root, delegate)) {
 }
 
 DragDropTracker::~DragDropTracker()  {
   capture_window_->ReleaseCapture();
 }
 
 void DragDropTracker::TakeCapture() {
   capture_window_->SetCapture();
 }
 
@@ skipping 24 matching lines @@
       ash::wm::GetRootWindowAt(location_in_screen),
       &target_root_location);
   return new ui::MouseEvent(event.type(),
                             target_location,
                             target_root_location,
                             event.flags());
 }
 
 }  // namespace internal
 }  // namespace ash