Moves WindowCycleList/Controller to ash/common

ash/wm/window_cycle_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/window_cycle_controller.h"
-
-#include "ash/common/metrics/task_switch_source.h"
-#include "ash/common/session/session_state_delegate.h"
-#include "ash/common/wm/mru_window_tracker.h"
-#include "ash/common/wm/window_cycle_event_filter.h"
-#include "ash/common/wm_shell.h"
-#include "ash/shell.h"
-#include "ash/wm/window_cycle_list.h"
-#include "base/metrics/histogram.h"
-
-namespace ash {
-
-namespace {
-
-// Returns the most recently active window from the |window_list| or nullptr
-// if the list is empty.
-WmWindow* GetActiveWindow(const MruWindowTracker::WindowList& window_list) {
-  return window_list.empty() ? nullptr : window_list[0];
-}
-
-}  // namespace
-
-//////////////////////////////////////////////////////////////////////////////
-// WindowCycleController, public:
-
-WindowCycleController::WindowCycleController() {}
-
-WindowCycleController::~WindowCycleController() {}
-
-// static
-bool WindowCycleController::CanCycle() {
-  // Prevent window cycling if the screen is locked or a modal dialog is open.
-  WmShell* wm_shell = WmShell::Get();
-  return !wm_shell->GetSessionStateDelegate()->IsScreenLocked() &&
-         !wm_shell->IsSystemModalWindowOpen() && !wm_shell->IsPinned();
-}
-
-void WindowCycleController::HandleCycleWindow(Direction direction) {
-  if (!CanCycle())
-    return;
-
-  if (!IsCycling())
-    StartCycling();
-
-  Step(direction);
-}
-
-void WindowCycleController::StartCycling() {
-  MruWindowTracker::WindowList window_list =
-      WmShell::Get()->mru_window_tracker()->BuildMruWindowList();
-
-  active_window_before_window_cycle_ = GetActiveWindow(window_list);
-
-  window_cycle_list_.reset(new WindowCycleList(window_list));
-  event_filter_ = WmShell::Get()->CreateWindowCycleEventFilter();
-  cycle_start_time_ = base::Time::Now();
-  WmShell::Get()->RecordUserMetricsAction(UMA_WINDOW_CYCLE);
-  UMA_HISTOGRAM_COUNTS_100("Ash.WindowCycleController.Items",
-                           window_list.size());
-}
-
-//////////////////////////////////////////////////////////////////////////////
-// WindowCycleController, private:
-
-void WindowCycleController::Step(Direction direction) {
-  DCHECK(window_cycle_list_.get());
-  window_cycle_list_->Step(direction);
-}
-
-void WindowCycleController::StopCycling() {
-  UMA_HISTOGRAM_COUNTS_100("Ash.WindowCycleController.SelectionDepth",
-                           window_cycle_list_->current_index() + 1);
-  window_cycle_list_.reset();
-
-  WmWindow* active_window_after_window_cycle = GetActiveWindow(
-      WmShell::Get()->mru_window_tracker()->BuildMruWindowList());
-
-  // Remove our key event filter.
-  event_filter_.reset();
-  UMA_HISTOGRAM_MEDIUM_TIMES("Ash.WindowCycleController.CycleTime",
-                             base::Time::Now() - cycle_start_time_);
-
-  if (active_window_after_window_cycle != nullptr &&
-      active_window_before_window_cycle_ != active_window_after_window_cycle) {
-    WmShell::Get()->RecordTaskSwitchMetric(
-        TaskSwitchSource::WINDOW_CYCLE_CONTROLLER);
-  }
-  active_window_before_window_cycle_ = nullptr;
-}
-
-}  // namespace ash