(fix landed) Reland of name MaximizeMode to TabletMode

ash/wm/tablet_mode/tablet_mode_window_manager.cc

Index: ash/wm/tablet_mode/tablet_mode_window_manager.cc
diff --git a/ash/wm/tablet_mode/tablet_mode_window_manager.cc b/ash/wm/tablet_mode/tablet_mode_window_manager.cc
new file mode 100644
index 0000000000000000000000000000000000000000..ee032c03b36457706da50c61e4bf327b651b2e62
--- /dev/null
+++ b/ash/wm/tablet_mode/tablet_mode_window_manager.cc
@@ -0,0 +1,306 @@
+// 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/tablet_mode/tablet_mode_window_manager.h"
+
+#include "ash/ash_switches.h"
+#include "ash/public/cpp/shell_window_ids.h"
+#include "ash/root_window_controller.h"
+#include "ash/session/session_state_delegate.h"
+#include "ash/shell.h"
+#include "ash/shell_port.h"
+#include "ash/wm/mru_window_tracker.h"
+#include "ash/wm/overview/window_selector_controller.h"
+#include "ash/wm/tablet_mode/tablet_mode_backdrop_delegate_impl.h"
+#include "ash/wm/tablet_mode/tablet_mode_event_handler.h"
+#include "ash/wm/tablet_mode/tablet_mode_window_state.h"
+#include "ash/wm/window_state.h"
+#include "ash/wm/wm_event.h"
+#include "ash/wm/workspace_controller.h"
+#include "base/command_line.h"
+#include "base/memory/ptr_util.h"
+#include "base/stl_util.h"
+#include "ui/aura/client/aura_constants.h"
+#include "ui/display/screen.h"
+
+namespace ash {
+
+namespace {
+
+// Exits overview mode if it is currently active.
+void CancelOverview() {
+  WindowSelectorController* controller =
+      Shell::Get()->window_selector_controller();
+  if (controller->IsSelecting())
+    controller->OnSelectionEnded();
+}
+
+}  // namespace
+
+TabletModeWindowManager::~TabletModeWindowManager() {
+  // Overview mode needs to be ended before exiting tablet mode to prevent
+  // transforming windows which are currently in
+  // overview: http://crbug.com/366605
+  CancelOverview();
+  for (aura::Window* window : added_windows_)
+    window->RemoveObserver(this);
+  added_windows_.clear();
+  Shell::Get()->RemoveShellObserver(this);
+  display::Screen::GetScreen()->RemoveObserver(this);
+  EnableBackdropBehindTopWindowOnEachDisplay(false);
+  RemoveWindowCreationObservers();
+  RestoreAllWindows();
+}
+
+int TabletModeWindowManager::GetNumberOfManagedWindows() {
+  return window_state_map_.size();
+}
+
+void TabletModeWindowManager::AddWindow(aura::Window* window) {
+  // Only add the window if it is a direct dependent of a container window
+  // and not yet tracked.
+  if (!ShouldHandleWindow(window) ||
+      base::ContainsKey(window_state_map_, window) ||
+      !IsContainerWindow(window->parent())) {
+    return;
+  }
+
+  MaximizeAndTrackWindow(window);
+}
+
+void TabletModeWindowManager::WindowStateDestroyed(aura::Window* window) {
+  // At this time ForgetWindow() should already have been called. If not,
+  // someone else must have replaced the "window manager's state object".
+  DCHECK(!window->HasObserver(this));
+
+  auto it = window_state_map_.find(window);
+  DCHECK(it != window_state_map_.end());
+  window_state_map_.erase(it);
+}
+
+void TabletModeWindowManager::OnOverviewModeStarting() {
+  SetDeferBoundsUpdates(true);
+}
+
+void TabletModeWindowManager::OnOverviewModeEnded() {
+  SetDeferBoundsUpdates(false);
+}
+
+void TabletModeWindowManager::OnWindowDestroying(aura::Window* window) {
+  if (IsContainerWindow(window)) {
+    // container window can be removed on display destruction.
+    window->RemoveObserver(this);
+    observed_container_windows_.erase(window);
+  } else if (base::ContainsValue(added_windows_, window)) {
+    // Added window was destroyed before being shown.
+    added_windows_.erase(window);
+    window->RemoveObserver(this);
+  } else {
+    // If a known window gets destroyed we need to remove all knowledge about
+    // it.
+    ForgetWindow(window);
+  }
+}
+
+void TabletModeWindowManager::OnWindowHierarchyChanged(
+    const HierarchyChangeParams& params) {
+  // A window can get removed and then re-added by a drag and drop operation.
+  if (params.new_parent && IsContainerWindow(params.new_parent) &&
+      !base::ContainsKey(window_state_map_, params.target)) {
+    // Don't register the window if the window is invisible. Instead,
+    // wait until it becomes visible because the client may update the
+    // flag to control if the window should be added.
+    if (!params.target->IsVisible()) {
+      if (!base::ContainsValue(added_windows_, params.target)) {
+        added_windows_.insert(params.target);
+        params.target->AddObserver(this);
+      }
+      return;
+    }
+    MaximizeAndTrackWindow(params.target);
+    // When the state got added, the "WM_EVENT_ADDED_TO_WORKSPACE" event got
+    // already sent and we have to notify our state again.
+    if (base::ContainsKey(window_state_map_, params.target)) {
+      wm::WMEvent event(wm::WM_EVENT_ADDED_TO_WORKSPACE);
+      wm::GetWindowState(params.target)->OnWMEvent(&event);
+    }
+  }
+}
+
+void TabletModeWindowManager::OnWindowPropertyChanged(aura::Window* window,
+                                                      const void* key,
+                                                      intptr_t old) {
+  // Stop managing |window| if the always-on-top property is added.
+  if (key == aura::client::kAlwaysOnTopKey &&
+      window->GetProperty(aura::client::kAlwaysOnTopKey)) {
+    ForgetWindow(window);
+  }
+}
+
+void TabletModeWindowManager::OnWindowBoundsChanged(
+    aura::Window* window,
+    const gfx::Rect& old_bounds,
+    const gfx::Rect& new_bounds) {
+  if (!IsContainerWindow(window))
+    return;
+  // Reposition all non maximizeable windows.
+  for (auto& pair : window_state_map_)
+    pair.second->UpdateWindowPosition(wm::GetWindowState(pair.first));
+}
+
+void TabletModeWindowManager::OnWindowVisibilityChanged(aura::Window* window,
+                                                        bool visible) {
+  // Skip if it's already managed.
+  if (base::ContainsKey(window_state_map_, window))
+    return;
+
+  if (IsContainerWindow(window->parent()) &&
+      base::ContainsValue(added_windows_, window) && visible) {
+    added_windows_.erase(window);
+    window->RemoveObserver(this);
+    MaximizeAndTrackWindow(window);
+    // When the state got added, the "WM_EVENT_ADDED_TO_WORKSPACE" event got
+    // already sent and we have to notify our state again.
+    if (base::ContainsKey(window_state_map_, window)) {
+      wm::WMEvent event(wm::WM_EVENT_ADDED_TO_WORKSPACE);
+      wm::GetWindowState(window)->OnWMEvent(&event);
+    }
+  }
+}
+
+void TabletModeWindowManager::OnDisplayAdded(const display::Display& display) {
+  DisplayConfigurationChanged();
+}
+
+void TabletModeWindowManager::OnDisplayRemoved(
+    const display::Display& display) {
+  DisplayConfigurationChanged();
+}
+
+void TabletModeWindowManager::OnDisplayMetricsChanged(const display::Display&,
+                                                      uint32_t) {
+  // Nothing to do here.
+}
+
+void TabletModeWindowManager::SetIgnoreWmEventsForExit() {
+  for (auto& pair : window_state_map_) {
+    pair.second->set_ignore_wm_events(true);
+  }
+}
+
+TabletModeWindowManager::TabletModeWindowManager() {
+  // The overview mode needs to be ended before the tablet mode is started. To
+  // guarantee the proper order, it will be turned off from here.
+  CancelOverview();
+
+  MaximizeAllWindows();
+  AddWindowCreationObservers();
+  EnableBackdropBehindTopWindowOnEachDisplay(true);
+  display::Screen::GetScreen()->AddObserver(this);
+  Shell::Get()->AddShellObserver(this);
+  event_handler_ = ShellPort::Get()->CreateTabletModeEventHandler();
+}
+
+void TabletModeWindowManager::MaximizeAllWindows() {
+  MruWindowTracker::WindowList windows =
+      Shell::Get()->mru_window_tracker()->BuildWindowListIgnoreModal();
+  // Add all existing MRU windows.
+  for (auto* window : windows)
+    MaximizeAndTrackWindow(window);
+}
+
+void TabletModeWindowManager::RestoreAllWindows() {
+  while (window_state_map_.size())
+    ForgetWindow(window_state_map_.begin()->first);
+}
+
+void TabletModeWindowManager::SetDeferBoundsUpdates(bool defer_bounds_updates) {
+  for (auto& pair : window_state_map_)
+    pair.second->SetDeferBoundsUpdates(defer_bounds_updates);
+}
+
+void TabletModeWindowManager::MaximizeAndTrackWindow(aura::Window* window) {
+  if (!ShouldHandleWindow(window))
+    return;
+
+  DCHECK(!base::ContainsKey(window_state_map_, window));
+  window->AddObserver(this);
+
+  // We create and remember a tablet mode state which will attach itself to
+  // the provided state object.
+  window_state_map_[window] = new TabletModeWindowState(window, this);
+}
+
+void TabletModeWindowManager::ForgetWindow(aura::Window* window) {
+  WindowToState::iterator it = window_state_map_.find(window);
+
+  // The following DCHECK could fail if our window state object was destroyed
+  // earlier by someone else. However - at this point there is no other client
+  // which replaces the state object and therefore this should not happen.
+  DCHECK(it != window_state_map_.end());
+  window->RemoveObserver(this);
+
+  // By telling the state object to revert, it will switch back the old
+  // State object and destroy itself, calling WindowStateDestroyed().
+  it->second->LeaveTabletMode(wm::GetWindowState(it->first));
+  DCHECK(!base::ContainsKey(window_state_map_, window));
+}
+
+bool TabletModeWindowManager::ShouldHandleWindow(aura::Window* window) {
+  DCHECK(window);
+
+  // Windows with the always-on-top property should be free-floating and thus
+  // not managed by us.
+  if (window->GetProperty(aura::client::kAlwaysOnTopKey))
+    return false;
+
+  // If the changing bounds in the maximized/fullscreen is allowed, then
+  // let the client manage it even in tablet mode.
+  if (wm::GetWindowState(window)->allow_set_bounds_direct())
+    return false;
+
+  return window->type() == aura::client::WINDOW_TYPE_NORMAL;
+}
+
+void TabletModeWindowManager::AddWindowCreationObservers() {
+  DCHECK(observed_container_windows_.empty());
+  // Observe window activations/creations in the default containers on all root
+  // windows.
+  for (aura::Window* root : Shell::GetAllRootWindows()) {
+    aura::Window* default_container =
+        root->GetChildById(kShellWindowId_DefaultContainer);
+    DCHECK(!base::ContainsKey(observed_container_windows_, default_container));
+    default_container->AddObserver(this);
+    observed_container_windows_.insert(default_container);
+  }
+}
+
+void TabletModeWindowManager::RemoveWindowCreationObservers() {
+  for (aura::Window* window : observed_container_windows_)
+    window->RemoveObserver(this);
+  observed_container_windows_.clear();
+}
+
+void TabletModeWindowManager::DisplayConfigurationChanged() {
+  EnableBackdropBehindTopWindowOnEachDisplay(false);
+  RemoveWindowCreationObservers();
+  AddWindowCreationObservers();
+  EnableBackdropBehindTopWindowOnEachDisplay(true);
+}
+
+bool TabletModeWindowManager::IsContainerWindow(aura::Window* window) {
+  return base::ContainsKey(observed_container_windows_, window);
+}
+
+void TabletModeWindowManager::EnableBackdropBehindTopWindowOnEachDisplay(
+    bool enable) {
+  // Inform the WorkspaceLayoutManager that we want to show a backdrop behind
+  // the topmost window of its container.
+  for (auto* controller : Shell::GetAllRootWindowControllers()) {
+    controller->workspace_controller()->SetBackdropDelegate(
+        enable ? base::MakeUnique<TabletModeBackdropDelegateImpl>() : nullptr);
+  }
+}
+
+}  // namespace ash