Allow Alt-Tab to move the focus to docked windows.

ash/accelerators/accelerator_controller_unittest.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/accelerators/accelerator_controller.h"
 
 #include "ash/accelerators/accelerator_table.h"
 #include "ash/accessibility_delegate.h"
 #include "ash/ash_switches.h"
 #include "ash/display/display_manager.h"
@@ skipping 635 matching lines @@
   gfx::Rect bounds = window->GetBoundsInScreen();
   EXPECT_NEAR(bounds.x() - work_area.x(),
               work_area.right() - bounds.right(),
               1);
   EXPECT_NEAR(bounds.y() - work_area.y(),
               work_area.bottom() - bounds.bottom(),
               1);
 
   // Add the window to docked container and try to center it.
   window->SetBounds(gfx::Rect(0, 0, 20, 20));
-  aura::Window* docked_container = Shell::GetContainer(
-      window->GetRootWindow(), kShellWindowId_DockedContainer);
-  docked_container->AddChild(window.get());
+  const wm::WMEvent event(wm::WM_EVENT_DOCK);
+  wm::GetWindowState(window.get())->OnWMEvent(&event);
+  EXPECT_EQ(kShellWindowId_DockedContainer, window->parent()->id());
+
   gfx::Rect docked_bounds = window->GetBoundsInScreen();
   GetController()->PerformActionIfEnabled(WINDOW_POSITION_CENTER);
   // It should not get centered and should remain docked.
   EXPECT_EQ(kShellWindowId_DockedContainer, window->parent()->id());
   EXPECT_EQ(docked_bounds.ToString(), window->GetBoundsInScreen().ToString());
 }
 
 TEST_F(AcceleratorControllerTest, AutoRepeat) {
   ui::Accelerator accelerator_a(ui::VKEY_A, ui::EF_CONTROL_DOWN);
   accelerator_a.set_type(ui::ET_KEY_PRESSED);
@@ skipping 738 matching lines @@
     wm::ActivateWindow(window.get());
     GetController()->PerformActionIfEnabled(WINDOW_MINIMIZE);
     delegate->TriggerAccessibilityAlert(ui::A11Y_ALERT_NONE);
     GetController()->PerformActionIfEnabled(kActionsNeedingWindow[i]);
     EXPECT_NE(delegate->GetLastAccessibilityAlert(),
               ui::A11Y_ALERT_WINDOW_NEEDED);
   }
 }
 
 }  // namespace ash