Revert of Refactor backdrop

ash/wm/workspace/backdrop_controller.cc

-// 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/workspace/backdrop_controller.h"
-
-#include "ash/accessibility_delegate.h"
-#include "ash/public/cpp/shell_window_ids.h"
-#include "ash/root_window_controller.h"
-#include "ash/shared/app_types.h"
-#include "ash/shell.h"
-#include "ash/system/tray/system_tray_notifier.h"
-#include "ash/wm/window_util.h"
-#include "ash/wm/workspace/backdrop_delegate.h"
-#include "ash/wm_window.h"
-#include "base/auto_reset.h"
-#include "chromeos/audio/chromeos_sounds.h"
-#include "ui/aura/client/aura_constants.h"
-#include "ui/compositor/layer.h"
-#include "ui/compositor/scoped_layer_animation_settings.h"
-#include "ui/views/widget/widget.h"
-#include "ui/wm/core/window_animations.h"
-#include "ui/wm/core/window_util.h"
-
-namespace ash {
-namespace {
-
-class BackdropEventHandler : public ui::EventHandler {
- public:
-  BackdropEventHandler() = default;
-  ~BackdropEventHandler() override = default;
-
-  // ui::EventHandler:
-  void OnEvent(ui::Event* event) override {
-    // If the event is targeted at the backdrop, it means the user has made an
-    // interaction that is outside the window's bounds and we want to capture
-    // it (usually when in spoken feedback mode). Handle the event (to prevent
-    // behind-windows from receiving it) and play an earcon to notify the user.
-    if (event->IsLocatedEvent()) {
-      switch (event->type()) {
-        case ui::ET_MOUSE_PRESSED:
-        case ui::ET_MOUSEWHEEL:
-        case ui::ET_TOUCH_PRESSED:
-        case ui::ET_POINTER_DOWN:
-        case ui::ET_POINTER_WHEEL_CHANGED:
-        case ui::ET_GESTURE_BEGIN:
-        case ui::ET_SCROLL:
-        case ui::ET_SCROLL_FLING_START:
-          Shell::Get()->accessibility_delegate()->PlayEarcon(
-              chromeos::SOUND_VOLUME_ADJUST);
-          break;
-        default:
-          break;
-      }
-      event->SetHandled();
-    }
-  }
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(BackdropEventHandler);
-};
-
-}  // namespace
-
-BackdropController::BackdropController(aura::Window* container)
-    : container_(container), in_restacking_(false) {
-  DCHECK(container_);
-  Shell::Get()->AddShellObserver(this);
-  Shell::Get()->system_tray_notifier()->AddAccessibilityObserver(this);
-}
-
-BackdropController::~BackdropController() {
-  Shell::Get()->system_tray_notifier()->RemoveAccessibilityObserver(this);
-  Shell::Get()->RemoveShellObserver(this);
-  // TODO: animations won't work right with mus: http://crbug.com/548396.
-  Hide();
-}
-
-void BackdropController::OnWindowAddedToLayout(aura::Window* child) {
-  UpdateBackdrop();
-}
-
-void BackdropController::OnWindowRemovedFromLayout(aura::Window* child) {
-  UpdateBackdrop();
-}
-
-void BackdropController::OnChildWindowVisibilityChanged(aura::Window* child,
-                                                        bool visible) {
-  UpdateBackdrop();
-}
-
-void BackdropController::OnWindowStackingChanged(aura::Window* window) {
-  UpdateBackdrop();
-}
-
-void BackdropController::OnPostWindowStateTypeChange(
-    wm::WindowState* window_state,
-    wm::WindowStateType old_type) {
-  UpdateBackdrop();
-}
-
-void BackdropController::SetBackdropDelegate(
-    std::unique_ptr<BackdropDelegate> delegate) {
-  delegate_ = std::move(delegate);
-  UpdateBackdrop();
-}
-
-void BackdropController::UpdateBackdrop() {
-  // Avoid recursive calls.
-  if (in_restacking_ || force_hidden_)
-    return;
-
-  aura::Window* window = GetTopmostWindowWithBackdrop();
-  if (!window) {
-    // Hide backdrop since no suitable window was found.
-    Hide();
-    return;
-  }
-  // We are changing the order of windows which will cause recursion.
-  base::AutoReset<bool> lock(&in_restacking_, true);
-  EnsureBackdropWidget();
-  UpdateAccessibilityMode();
-
-  if (window == backdrop_window_ && backdrop_->IsVisible())
-    return;
-  if (window->GetRootWindow() != backdrop_window_->GetRootWindow())
-    return;
-
-  if (!backdrop_->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(backdrop_window_, window);
-  container_->StackChildAbove(window, backdrop_window_);
-}
-
-void BackdropController::OnOverviewModeStarting() {
-  force_hidden_ = true;
-  Hide();
-}
-
-void BackdropController::OnOverviewModeEnded() {
-  force_hidden_ = false;
-  UpdateBackdrop();
-}
-
-void BackdropController::OnAccessibilityModeChanged(
-    AccessibilityNotificationVisibility notify) {
-  UpdateBackdrop();
-}
-
-void BackdropController::EnsureBackdropWidget() {
-  if (backdrop_)
-    return;
-
-  backdrop_ = 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_->id());
-  RootWindowController::ForWindow(container_)
-      ->ConfigureWidgetInitParamsForContainer(backdrop_, container_->id(),
-                                              &params);
-  backdrop_->Init(params);
-  backdrop_window_ = backdrop_->GetNativeWindow();
-  backdrop_window_->SetName("Backdrop");
-  ::wm::SetWindowVisibilityAnimationType(
-      backdrop_window_, ::wm::WINDOW_VISIBILITY_ANIMATION_TYPE_FADE);
-  backdrop_window_->layer()->SetColor(SK_ColorBLACK);
-}
-
-void BackdropController::UpdateAccessibilityMode() {
-  if (!backdrop_)
-    return;
-
-  bool enabled =
-      Shell::Get()->accessibility_delegate()->IsSpokenFeedbackEnabled();
-  if (enabled) {
-    if (!backdrop_event_handler_) {
-      backdrop_event_handler_ = base::MakeUnique<BackdropEventHandler>();
-      original_event_handler_ =
-          backdrop_window_->SetTargetHandler(backdrop_event_handler_.get());
-    }
-  } else if (backdrop_event_handler_) {
-    backdrop_window_->SetTargetHandler(original_event_handler_);
-    backdrop_event_handler_.reset();
-  }
-}
-
-aura::Window* BackdropController::GetTopmostWindowWithBackdrop() {
-  // ARC app should always have a backdrop when spoken feedback is enabled.
-  if (Shell::Get()->accessibility_delegate()->IsSpokenFeedbackEnabled()) {
-    aura::Window* active_window = wm::GetActiveWindow();
-    if (active_window && active_window->parent() == container_ &&
-        active_window->GetProperty(aura::client::kAppType) ==
-            static_cast<int>(AppType::ARC_APP)) {
-      return active_window;
-    }
-  }
-
-  const aura::Window::Windows windows = container_->children();
-  for (auto window_iter = windows.rbegin(); window_iter != windows.rend();
-       ++window_iter) {
-    aura::Window* window = *window_iter;
-    if (window != backdrop_window_ && window->layer()->GetTargetVisibility() &&
-        window->type() == ui::wm::WINDOW_TYPE_NORMAL &&
-        ::wm::CanActivateWindow(window) && WindowShouldHaveBackdrop(window)) {
-      return window;
-    }
-  }
-  return nullptr;
-}
-
-bool BackdropController::WindowShouldHaveBackdrop(aura::Window* window) {
-  if (window->GetAllPropertyKeys().count(aura::client::kHasBackdrop) &&
-      window->GetProperty(aura::client::kHasBackdrop)) {
-    return true;
-  }
-  return delegate_ ? delegate_->HasBackdrop(window) : false;
-}
-
-void BackdropController::Show() {
-  backdrop_->Show();
-  backdrop_->SetFullscreen(true);
-}
-
-void BackdropController::Hide() {
-  if (!backdrop_)
-    return;
-  backdrop_->Close();
-  backdrop_ = nullptr;
-  backdrop_window_ = nullptr;
-  original_event_handler_ = nullptr;
-  backdrop_event_handler_.reset();
-}
-
-}  // namespace ash