Revert "Enable ash window cycle UI by default."

ash/common/wm/window_cycle_list.cc

Index: ash/common/wm/window_cycle_list.cc
diff --git a/ash/common/wm/window_cycle_list.cc b/ash/common/wm/window_cycle_list.cc
index 845dcaa5d21059b9b6806c50a3a8db1944eea0c4..2c0ec797d0bb825fdd3e487b7947a5ec845bb4d6 100644
--- a/ash/common/wm/window_cycle_list.cc
+++ b/ash/common/wm/window_cycle_list.cc
@@ -30,10 +30,6 @@
 
 namespace ash {
 
-namespace {
-
-bool g_disable_initial_delay = false;
-
 // Returns the window immediately below |window| in the current container.
 WmWindow* GetWindowBelow(WmWindow* window) {
   WmWindow* parent = window->GetParent();
@@ -65,8 +61,6 @@ class LayerFillBackgroundPainter : public views::Background {
   DISALLOW_COPY_AND_ASSIGN(LayerFillBackgroundPainter);
 };
 
-}  // namespace
-
 // This class restores and moves a window to the front of the stacking order for
 // the duration of the class's scope.
 class ScopedShowWindow : public WmWindowObserver {
@@ -308,28 +302,16 @@ class WindowCycleView : public views::WidgetDelegateView {
     target_window_ = target;
     if (GetWidget()) {
       Layout();
-      if (target_window_) {
-        // In the window destruction case, we may have already removed the
-        // focused view and hence not be the focused window. We should still
-        // always be active, though.
-        DCHECK_EQ(ash::WmShell::Get()->GetActiveWindow()->GetInternalWidget(),
-                  GetWidget());
-        window_view_map_[target_window_]->RequestFocus();
-      }
+      DCHECK(Contains(GetFocusManager()->GetFocusedView()));
+      window_view_map_[target_window_]->RequestFocus();
     }
   }
 
   void HandleWindowDestruction(WmWindow* destroying_window,
                                WmWindow* new_target) {
     auto view_iter = window_view_map_.find(destroying_window);
-    views::View* parent = view_iter->second->parent();
-    DCHECK_EQ(mirror_container_, parent);
-    parent->RemoveChildView(view_iter->second);
+    view_iter->second->parent()->RemoveChildView(view_iter->second);
     window_view_map_.erase(view_iter);
-    // With one of its children now gone, we must re-layout |mirror_container_|.
-    // This must happen before SetTargetWindow() to make sure our own Layout()
-    // works correctly when it's calculating highlight bounds.
-    parent->Layout();
     SetTargetWindow(new_target);
   }
 
@@ -433,26 +415,19 @@ void ScopedShowWindow::OnWindowTreeChanging(WmWindow* window,
 
 WindowCycleList::WindowCycleList(const WindowList& windows)
     : windows_(windows), current_index_(0), cycle_view_(nullptr) {
-  if (!ShouldShowUi())
-    WmShell::Get()->mru_window_tracker()->SetIgnoreActivations(true);
+  WmShell::Get()->mru_window_tracker()->SetIgnoreActivations(true);
 
   for (WmWindow* window : windows_)
     window->AddObserver(this);
 
   if (ShouldShowUi()) {
-    if (g_disable_initial_delay) {
-      InitWindowCycleView();
-    } else {
-      show_ui_timer_.Start(FROM_HERE, base::TimeDelta::FromMilliseconds(150),
-                           this, &WindowCycleList::InitWindowCycleView);
-    }
+    show_ui_timer_.Start(FROM_HERE, base::TimeDelta::FromMilliseconds(150),
+                         this, &WindowCycleList::InitWindowCycleView);
   }
 }
 
 WindowCycleList::~WindowCycleList() {
-  if (!ShouldShowUi())
-    WmShell::Get()->mru_window_tracker()->SetIgnoreActivations(false);
-
+  WmShell::Get()->mru_window_tracker()->SetIgnoreActivations(false);
   for (WmWindow* window : windows_)
     window->RemoveObserver(this);
 
@@ -500,11 +475,6 @@ void WindowCycleList::Step(WindowCycleController::Direction direction) {
   }
 }
 
-// static
-void WindowCycleList::DisableInitialDelayForTesting() {
-  g_disable_initial_delay = true;
-}
-
 void WindowCycleList::OnWindowDestroying(WmWindow* window) {
   window->RemoveObserver(this);
 
@@ -531,7 +501,9 @@ void WindowCycleList::OnWindowDestroying(WmWindow* window) {
 }
 
 bool WindowCycleList::ShouldShowUi() {
-  return windows_.size() > 1;
+  return windows_.size() > 1 &&
+         base::CommandLine::ForCurrentProcess()->HasSwitch(
+             switches::kAshEnableWindowCycleUi);
 }
 
 void WindowCycleList::InitWindowCycleView() {