Enable ash window cycle UI by default.

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/common/accelerators/accelerator_controller.h"
 
 #include "ash/aura/wm_window_aura.h"
 #include "ash/common/accelerators/accelerator_table.h"
 #include "ash/common/accessibility_delegate.h"
 #include "ash/common/accessibility_types.h"
@@ skipping 1106 matching lines @@
   ui::test::EventGenerator& generator = GetEventGenerator();
 #if defined(OS_CHROMEOS)
   // Power key (reserved) should always be handled.
   LockStateController::TestApi test_api(
       Shell::GetInstance()->lock_state_controller());
   EXPECT_FALSE(test_api.is_animating_lock());
   generator.PressKey(ui::VKEY_POWER, ui::EF_NONE);
   EXPECT_TRUE(test_api.is_animating_lock());
 #endif
 
+  auto press_alt_tab = [&generator]() {

[sky, 2016/08/13 15:56:06]

optional: press_alt_tab is easy to assume means only press. Maybe
press_and_release_alt_tab?

[Evan Stade, 2016/08/14 01:43:12]

Done.

+    generator.PressKey(ui::VKEY_TAB, ui::EF_ALT_DOWN);
+    // Release the alt key to complete Alt+Tab.
+    generator.ReleaseKey(ui::VKEY_MENU, ui::EF_NONE);
+  };
+
   // A fullscreen window can consume ALT-TAB (preferred).
   ASSERT_EQ(w1, wm::GetActiveWindow());
-  generator.PressKey(ui::VKEY_TAB, ui::EF_ALT_DOWN);
+  press_alt_tab();
   ASSERT_EQ(w1, wm::GetActiveWindow());
   ASSERT_NE(w2, wm::GetActiveWindow());
 
   // ALT-TAB is non repeatable. Press A to cancel the
   // repeat record.
   generator.PressKey(ui::VKEY_A, ui::EF_NONE);
   generator.ReleaseKey(ui::VKEY_A, ui::EF_NONE);
 
   // A normal window shouldn't consume preferred accelerator.
   wm::WMEvent normal(wm::WM_EVENT_NORMAL);
   w1_state->OnWMEvent(&normal);
   ASSERT_FALSE(w1_state->IsFullscreen());
 
   EXPECT_EQ(w1, wm::GetActiveWindow());
-  generator.PressKey(ui::VKEY_TAB, ui::EF_ALT_DOWN);
+  press_alt_tab();
   ASSERT_NE(w1, wm::GetActiveWindow());
   ASSERT_EQ(w2, wm::GetActiveWindow());
 }
 
 TEST_F(PreferredReservedAcceleratorsTest, AcceleratorsWithPinned) {
   aura::Window* w1 = CreateTestWindowInShellWithId(0);
   aura::Window* w2 = CreateTestWindowInShellWithId(1);
   wm::ActivateWindow(w1);
 
   {
@@ skipping 252 matching lines @@
     EXPECT_TRUE(IsMessageCenterEmpty());
 
     // If the action is LOCK_SCREEN, we must reset the state by unlocking the
     // screen before we proceed testing the rest of accelerators.
     ResetStateIfNeeded();
   }
 }
 #endif  // defined(OS_CHROMEOS)
 
 }  // namespace ash