Add persisted preference for projection touch HUD

A new preference is created showing if the projection touch HUD is
enabled or not. This preference is per-user and unsyncable. It is not
exposed anywhere in the UI, but can be toggled using the Ctrl+Alt+9
accelerator combination.

BUG=233567

Review URL: https://chromiumcodereview.appspot.com/18163006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@210516 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 45 insertions, 40 deletions

diff --git a/ash/root_window_controller.cc b/ash/root_window_controller.cc
index 0bacb01..82ff30d 100644
--- a/ash/root_window_controller.cc
+++ b/ash/root_window_controller.cc
@@ -209,18 +209,6 @@ RootWindowController* RootWindowController::ForActiveRootWindow() {
   return GetRootWindowController(Shell::GetActiveRootWindow());
 }
 
-void RootWindowController::EnableTouchHudProjection() {
-  if (touch_hud_projection_)
-    return;
-  set_touch_hud_projection(new TouchHudProjection(root_window_.get()));
-}
-
-void RootWindowController::DisableTouchHudProjection() {
-  if (!touch_hud_projection_)
-    return;
-  touch_hud_projection_->Remove();
-}
-
 void RootWindowController::SetWallpaperController(
     DesktopBackgroundWidgetController* controller) {
   wallpaper_controller_.reset(controller);
@@ -234,6 +222,8 @@ void RootWindowController::SetAnimatingWallpaperController(
 }
 
 void RootWindowController::Shutdown() {
+  Shell::GetInstance()->RemoveShellObserver(this);
+
   if (animating_wallpaper_controller_.get())
     animating_wallpaper_controller_->StopAnimating();
   wallpaper_controller_.reset();
@@ -298,6 +288,8 @@ void RootWindowController::Init(bool first_run_after_boot) {
       GetSystemModalLayoutManager(NULL)->has_modal_background()) {
     GetSystemModalLayoutManager(NULL)->CreateModalBackground();
   }
+
+  Shell::GetInstance()->AddShellObserver(this);
 }
 
 void RootWindowController::ShowLauncher() {
@@ -314,10 +306,6 @@ void RootWindowController::OnLauncherCreated() {
     docked_layout_manager_->SetLauncher(shelf_->launcher());
 }
 
-void RootWindowController::OnLoginStateChanged(user::LoginStatus status) {
-  shelf_->shelf_layout_manager()->UpdateVisibilityState();
-}
-
 void RootWindowController::UpdateAfterLoginStatusChange(
     user::LoginStatus status) {
   if (shelf_->status_area_widget())
@@ -708,5 +696,28 @@ void RootWindowController::CreateContainersInRootWindow(
                   "PowerButtonAnimationContainer", root_window) ;
 }
 
+void RootWindowController::EnableTouchHudProjection() {
+  if (touch_hud_projection_)
+    return;
+  set_touch_hud_projection(new TouchHudProjection(root_window_.get()));
+}
+
+void RootWindowController::DisableTouchHudProjection() {
+  if (!touch_hud_projection_)
+    return;
+  touch_hud_projection_->Remove();
+}
+
+void RootWindowController::OnLoginStateChanged(user::LoginStatus status) {
+  shelf_->shelf_layout_manager()->UpdateVisibilityState();
+}
+
+void RootWindowController::OnTouchHudProjectionToggled(bool enabled) {
+  if (enabled)
+    EnableTouchHudProjection();
+  else
+    DisableTouchHudProjection();
+}
+
 }  // namespace internal
 }  // namespace ash
diff --git a/ash/root_window_controller.h b/ash/root_window_controller.h
index 393dcb3..920c553 100644
--- a/ash/root_window_controller.h
+++ b/ash/root_window_controller.h
@@ -9,6 +9,7 @@
 
 #include "ash/ash_export.h"
 #include "ash/shelf/shelf_types.h"
+#include "ash/shell_observer.h"
 #include "ash/system/user/login_status.h"
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
@@ -68,10 +69,10 @@ class WorkspaceController;
 // deleted upon the deletion of the root window.  The RootWindowController
 // for particular root window is stored as a property and can be obtained
 // using |GetRootWindowController(aura::RootWindow*)| function.
-class ASH_EXPORT RootWindowController {
+class ASH_EXPORT RootWindowController : public ShellObserver {
  public:
   explicit RootWindowController(aura::RootWindow* root_window);
-  ~RootWindowController();
+  virtual ~RootWindowController();
 
   // Returns a RootWindowController that has a launcher for given
   // |window|. This returns the RootWindowController for the |window|'s
@@ -122,12 +123,6 @@ class ASH_EXPORT RootWindowController {
     touch_hud_projection_ = hud;
   }
 
-  // Enables projection touch HUD.
-  void EnableTouchHudProjection();
-
-  // Disables projection touch HUD.
-  void DisableTouchHudProjection();
-
   DesktopBackgroundWidgetController* wallpaper_controller() {
     return wallpaper_controller_.get();
   }
@@ -173,9 +168,6 @@ class ASH_EXPORT RootWindowController {
   // Called when the launcher associated with this root window is created.
   void OnLauncherCreated();
 
-  // Called when the user logs in.
-  void OnLoginStateChanged(user::LoginStatus status);
-
   // Called when the login status changes after login (such as lock/unlock).
   // TODO(oshima): Investigate if we can merge this and |OnLoginStateChanged|.
   void UpdateAfterLoginStatusChange(user::LoginStatus status);
@@ -228,6 +220,16 @@ class ASH_EXPORT RootWindowController {
   // Initializes the virtual keyboard.
   void InitKeyboard();
 
+  // Enables projection touch HUD.
+  void EnableTouchHudProjection();
+
+  // Disables projection touch HUD.
+  void DisableTouchHudProjection();
+
+  // Overridden from ShellObserver.
+  virtual void OnLoginStateChanged(user::LoginStatus status) OVERRIDE;
+  virtual void OnTouchHudProjectionToggled(bool enabled) OVERRIDE;
+
   scoped_ptr<aura::RootWindow> root_window_;
   RootWindowLayoutManager* root_window_layout_;
 
diff --git a/ash/shell.cc b/ash/shell.cc
index 1610ae3..8d3b3bb 100644
--- a/ash/shell.cc
+++ b/ash/shell.cc
@@ -715,10 +715,6 @@ void Shell::SetDisplayWorkAreaInsets(Window* contains,
 
 void Shell::OnLoginStateChanged(user::LoginStatus status) {
   FOR_EACH_OBSERVER(ShellObserver, observers_, OnLoginStateChanged(status));
-  RootWindowControllerList controllers = GetAllRootWindowControllers();
-  for (RootWindowControllerList::iterator iter = controllers.begin();
-       iter != controllers.end(); ++iter)
-    (*iter)->OnLoginStateChanged(status);
 }
 
 void Shell::UpdateAfterLoginStatusChange(user::LoginStatus status) {
@@ -854,16 +850,9 @@ void Shell::SetTouchHudProjectionEnabled(bool enabled) {
   if (is_touch_hud_projection_enabled_ == enabled)
     return;
 
-  RootWindowList roots = GetInstance()->GetAllRootWindows();
-  for (RootWindowList::iterator iter = roots.begin(); iter != roots.end();
-      ++iter) {
-    internal::RootWindowController* controller = GetRootWindowController(*iter);
-    if (enabled)
-      controller->EnableTouchHudProjection();
-    else
-      controller->DisableTouchHudProjection();
-  }
   is_touch_hud_projection_enabled_ = enabled;
+  FOR_EACH_OBSERVER(ShellObserver, observers_,
+                    OnTouchHudProjectionToggled(enabled));
 }
 
 void Shell::InitRootWindowForSecondaryDisplay(aura::RootWindow* root) {
diff --git a/ash/shell_observer.h b/ash/shell_observer.h
index 0bdd934..060e30a 100644
--- a/ash/shell_observer.h
+++ b/ash/shell_observer.h
@@ -32,6 +32,9 @@ class ASH_EXPORT ShellObserver {
   // Invoked when the shelf alignment in |root_window| is changed.
   virtual void OnShelfAlignmentChanged(aura::RootWindow* root_window) {}
 
+  // Invoked when the projection touch HUD is toggled.
+  virtual void OnTouchHudProjectionToggled(bool enabled) {}
+
  protected:
   virtual ~ShellObserver() {}
 };