Revert of Refactor backdrop

ash/wm/maximize_mode/workspace_backdrop_delegate.cc

Index: ash/wm/maximize_mode/workspace_backdrop_delegate.cc
diff --git a/ash/wm/maximize_mode/workspace_backdrop_delegate.cc b/ash/wm/maximize_mode/workspace_backdrop_delegate.cc
new file mode 100644
index 0000000000000000000000000000000000000000..496cc7f131de362d5e053467b6b828e1b0a40257
--- /dev/null
+++ b/ash/wm/maximize_mode/workspace_backdrop_delegate.cc
@@ -0,0 +1,133 @@
+// Copyright 2014 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/wm/maximize_mode/workspace_backdrop_delegate.h"
+
+#include "ash/public/cpp/shell_window_ids.h"
+#include "ash/root_window_controller.h"
+#include "ash/wm/workspace/workspace_layout_manager_backdrop_delegate.h"
+#include "ash/wm_window.h"
+#include "base/auto_reset.h"
+#include "ui/compositor/layer.h"
+#include "ui/compositor/scoped_layer_animation_settings.h"
+#include "ui/views/background.h"
+#include "ui/views/widget/widget.h"
+#include "ui/wm/core/window_animations.h"
+#include "ui/wm/core/window_util.h"
+
+namespace ash {
+namespace {
+
+// The opacity of the backdrop.
+const float kBackdropOpacity = 1.0f;
+
+}  // namespace
+
+WorkspaceBackdropDelegate::WorkspaceBackdropDelegate(WmWindow* container)
+    : container_(container), in_restacking_(false) {
+  background_ = new views::Widget;
+  views::Widget::InitParams params(
+      views::Widget::InitParams::TYPE_WINDOW_FRAMELESS);
+  params.bounds = container_->GetBoundsInScreen();
+  params.layer_type = ui::LAYER_SOLID_COLOR;
+  params.name = "WorkspaceBackdropDelegate";
+  // To disallow the MRU list from picking this window up it should not be
+  // activateable.
+  params.activatable = views::Widget::InitParams::ACTIVATABLE_NO;
+  DCHECK_NE(kShellWindowId_Invalid, container_->aura_window()->id());
+  container_->GetRootWindowController()->ConfigureWidgetInitParamsForContainer(
+      background_, container_->aura_window()->id(), &params);
+  background_->Init(params);
+  background_window_ = WmWindow::Get(background_->GetNativeWindow());
+  // Do not use the animation system. We don't want the bounds animation and
+  // opacity needs to get set to |kBackdropOpacity|.
+  background_window_->SetVisibilityAnimationTransition(::wm::ANIMATE_NONE);
+  background_window_->GetLayer()->SetColor(SK_ColorBLACK);
+  // Make sure that the layer covers visibly everything - including the shelf.
+  background_window_->GetLayer()->SetBounds(params.bounds);
+  DCHECK(background_window_->GetBounds() == params.bounds);
+  Show();
+  RestackBackdrop();
+}
+
+WorkspaceBackdropDelegate::~WorkspaceBackdropDelegate() {
+  // TODO: animations won't work right with mus: http://crbug.com/548396.
+  ::wm::ScopedHidingAnimationSettings hiding_settings(
+      background_->GetNativeView());
+  background_->Close();
+  background_window_->GetLayer()->SetOpacity(0.0f);
+}
+
+void WorkspaceBackdropDelegate::OnWindowAddedToLayout(WmWindow* child) {
+  RestackBackdrop();
+}
+
+void WorkspaceBackdropDelegate::OnWindowRemovedFromLayout(WmWindow* child) {
+  RestackBackdrop();
+}
+
+void WorkspaceBackdropDelegate::OnChildWindowVisibilityChanged(WmWindow* child,
+                                                               bool visible) {
+  RestackBackdrop();
+}
+
+void WorkspaceBackdropDelegate::OnWindowStackingChanged(WmWindow* window) {
+  RestackBackdrop();
+}
+
+void WorkspaceBackdropDelegate::OnPostWindowStateTypeChange(
+    wm::WindowState* window_state,
+    wm::WindowStateType old_type) {
+  RestackBackdrop();
+}
+
+void WorkspaceBackdropDelegate::RestackBackdrop() {
+  // Avoid recursive calls.
+  if (in_restacking_)
+    return;
+
+  WmWindow* window = GetCurrentTopWindow();
+  if (!window) {
+    // Hide backdrop since no suitable window was found.
+    background_->Hide();
+    return;
+  }
+  if (window == background_window_ && background_->IsVisible())
+    return;
+  if (window->GetRootWindow() != background_window_->GetRootWindow())
+    return;
+  // We are changing the order of windows which will cause recursion.
+  base::AutoReset<bool> lock(&in_restacking_, true);
+  if (!background_->IsVisible())
+    Show();
+  // Since the backdrop needs to be immediately behind the window and the
+  // stacking functions only guarantee a "it's above or below", we need
+  // to re-arrange the two windows twice.
+  container_->StackChildAbove(background_window_, window);
+  container_->StackChildAbove(window, background_window_);
+}
+
+WmWindow* WorkspaceBackdropDelegate::GetCurrentTopWindow() {
+  const WmWindow::Windows windows = container_->GetChildren();
+  for (auto window_iter = windows.rbegin(); window_iter != windows.rend();
+       ++window_iter) {
+    WmWindow* window = *window_iter;
+    if (window->GetTargetVisibility() &&
+        window->GetType() == ui::wm::WINDOW_TYPE_NORMAL &&
+        window->CanActivate())
+      return window;
+  }
+  return nullptr;
+}
+
+void WorkspaceBackdropDelegate::Show() {
+  background_window_->GetLayer()->SetOpacity(0.0f);
+  background_->Show();
+  background_->SetFullscreen(true);
+  ui::ScopedLayerAnimationSettings settings(
+      background_window_->GetLayer()->GetAnimator());
+  background_window_->GetLayer()->SetOpacity(kBackdropOpacity);
+}
+
+}  // namespace ash