[VK] Remove unnecessary observers of OnVirtualKeyboardStateChanged.

Some classes listen to ShellObserver::OnVirtualKeyboardStateChanged in
order to add/remove KeyboardController observer when the keyboard is
enabled/disabled. However, with the simplified KeyboardController
lifetimes, we can add/remove observers whenever.

So we just add an observer in the constructor and remove it in the
destructor.

After this change, there will be no more observers of
OnVirtualKeyboardStateChanged.

Bug: 731537
Change-Id: I7274484229ff5f64ac973806e565f178a271094f
Reviewed-on: https://chromium-review.googlesource.com/1101598Reviewed-by: James Cook <jamescook@chromium.org>
Commit-Queue: Darren Shen <shend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#567918}

ash/app_list/app_list_controller_impl.cc

@@ -41,7 +41,6 @@ namespace ash {
 
 AppListControllerImpl::AppListControllerImpl()
     : presenter_(std::make_unique<AppListPresenterDelegateImpl>(this)),
-      keyboard_observer_(this),
       is_home_launcher_enabled_(app_list::features::IsHomeLauncherEnabled()) {
   model_.AddObserver(this);
 
@@ -63,9 +62,11 @@ AppListControllerImpl::AppListControllerImpl()
   Shell::Get()->tablet_mode_controller()->AddObserver(this);
   Shell::Get()->wallpaper_controller()->AddObserver(this);
   Shell::Get()->AddShellObserver(this);
+  keyboard::KeyboardController::Get()->AddObserver(this);
 }
 
 AppListControllerImpl::~AppListControllerImpl() {
+  keyboard::KeyboardController::Get()->RemoveObserver(this);
   Shell::Get()->RemoveShellObserver(this);
   Shell::Get()->wallpaper_controller()->RemoveObserver(this);
   Shell::Get()->tablet_mode_controller()->RemoveObserver(this);
@@ -446,18 +447,6 @@ void AppListControllerImpl::FlushForTesting() {
   bindings_.FlushForTesting();
 }
 
-void AppListControllerImpl::OnVirtualKeyboardStateChanged(
-    bool activated,
-    aura::Window* root_window) {
-  auto* keyboard_controller = keyboard::KeyboardController::Get();
-  if (!keyboard_controller->enabled())
-    return;
-  if (activated && !keyboard_observer_.IsObserving(keyboard_controller))
-    keyboard_observer_.Add(keyboard_controller);
-  else if (!activated && keyboard_observer_.IsObserving(keyboard_controller))
-    keyboard_observer_.Remove(keyboard_controller);
-}
-
 void AppListControllerImpl::OnOverviewModeStarting() {
   in_overview_mode_ = true;
   if (!IsHomeLauncherEnabledInTabletMode()) {

ash/app_list/app_list_controller_impl.h

@@ -22,7 +22,6 @@
 #include "ash/shell_observer.h"
 #include "ash/wallpaper/wallpaper_controller_observer.h"
 #include "ash/wm/tablet_mode/tablet_mode_observer.h"
-#include "base/scoped_observer.h"
 #include "components/sync/model/string_ordinal.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 #include "mojo/public/cpp/bindings/interface_ptr_set.h"
@@ -171,8 +170,6 @@ class ASH_EXPORT AppListControllerImpl
   void FlushForTesting();
 
   // ShellObserver:
-  void OnVirtualKeyboardStateChanged(bool activated,
-                                     aura::Window* root_window) override;
   void OnOverviewModeStarting() override;
   void OnOverviewModeEnding() override;
 
@@ -221,10 +218,6 @@ class ASH_EXPORT AppListControllerImpl
   std::unique_ptr<app_list::AnswerCardContentsRegistry>
       answer_card_contents_registry_;
 
-  ScopedObserver<keyboard::KeyboardController,
-                 keyboard::KeyboardControllerObserver>
-      keyboard_observer_;
-
   // Whether the on-screen keyboard is shown.
   bool onscreen_keyboard_shown_ = false;
 

ash/root_window_controller.cc

@@ -570,7 +570,6 @@ void RootWindowController::ActivateKeyboard(
   aura::Window* keyboard_window = keyboard_controller->GetContainerWindow();
   DCHECK(!keyboard_window->parent());
 
-  Shell::Get()->NotifyVirtualKeyboardActivated(true, GetRootWindow());
   aura::Window* vk_container =
       GetContainer(kShellWindowId_VirtualKeyboardContainer);
   DCHECK(vk_container);
@@ -597,7 +596,6 @@ void RootWindowController::DeactivateKeyboard(
     DCHECK(vk_container);
     DCHECK_EQ(vk_container, keyboard_window->parent());
     vk_container->RemoveChild(keyboard_window);
-    Shell::Get()->NotifyVirtualKeyboardActivated(false, GetRootWindow());
   }
 }
 

ash/shell.cc

@@ -640,12 +640,6 @@ void Shell::NotifyPinnedStateChanged(aura::Window* pinned_window) {
     observer.OnPinnedStateChanged(pinned_window);
 }
 
-void Shell::NotifyVirtualKeyboardActivated(bool activated,
-                                           aura::Window* root_window) {
-  for (auto& observer : shell_observers_)
-    observer.OnVirtualKeyboardStateChanged(activated, root_window);
-}
-
 void Shell::NotifyShelfCreatedForRootWindow(aura::Window* root_window) {
   for (auto& observer : shell_observers_)
     observer.OnShelfCreatedForRootWindow(root_window);

ash/shell.h

@@ -643,11 +643,6 @@ class ASH_EXPORT Shell : public SessionObserver,
   // Notifies observers that |pinned_window| changed its pinned window state.
   void NotifyPinnedStateChanged(aura::Window* pinned_window);
 
-  // Notifies observers that the virtual keyboard has been
-  // activated/deactivated for |root_window|.
-  void NotifyVirtualKeyboardActivated(bool activated,
-                                      aura::Window* root_window);
-
   // Notifies observers that the shelf was created for |root_window|.
   // TODO(jamescook): Move to Shelf.
   void NotifyShelfCreatedForRootWindow(aura::Window* root_window);

ash/shell_observer.h

@@ -71,10 +71,6 @@ class ASH_EXPORT ShellObserver {
   // Called when dicatation is ended.
   virtual void OnDictationEnded() {}
 
-  // Called when keyboard is activated/deactivated in |root_window|.
-  virtual void OnVirtualKeyboardStateChanged(bool activated,
-                                             aura::Window* root_window) {}
-
   // Called when a new KeyboardController is created.
   virtual void OnKeyboardControllerCreated() {}
 

chrome/browser/chromeos/login/ui/webui_login_view.cc

@@ -127,11 +127,7 @@ WebUILoginView::WebUILoginView(const WebViewSettings& settings)
   // TODO(mash): Support virtual keyboard under MASH. There is no
   // KeyboardController in the browser process under MASH.
   if (!ash_util::IsRunningInMash()) {
-    if (keyboard::KeyboardController::Get()->enabled())
-      keyboard::KeyboardController::Get()->AddObserver(this);
-    // TODO(crbug.com/648733): OnVirtualKeyboardStateChanged not supported in
-    // mash
-    ash::Shell::Get()->AddShellObserver(this);
+    keyboard::KeyboardController::Get()->AddObserver(this);
   } else {
     NOTIMPLEMENTED();
   }
@@ -215,20 +211,12 @@ WebUILoginView::~WebUILoginView() {
   for (auto& observer : observer_list_)
     observer.OnHostDestroying();
 
-  // TODO(crbug.com/648733): OnVirtualKeyboardStateChanged not supported in mash
-  if (!ash_util::IsRunningInMash()) {
-    ash::Shell::Get()->RemoveShellObserver(this);
-    if (keyboard::KeyboardController::Get()->enabled())
-      keyboard::KeyboardController::Get()->RemoveObserver(this);
-  }
-
   if (!ash_util::IsRunningInMash()) {
     ash::Shell::Get()->system_tray_notifier()->RemoveSystemTrayFocusObserver(
         this);
-  }
-
-  if (!ash_util::IsRunningInMash())
     ash::Shell::Get()->accelerator_controller()->UnregisterAll(this);
+    keyboard::KeyboardController::Get()->RemoveObserver(this);
+  }
 
   // Clear any delegates we have set on the WebView.
   WebContents* web_contents = web_view()->GetWebContents();
@@ -458,23 +446,6 @@ void WebUILoginView::ClearLockScreenAppFocusCyclerDelegate() {
   delegates_lock_screen_app_focus_cycle_ = false;
 }
 
-////////////////////////////////////////////////////////////////////////////////
-// ash::ShellObserver:
-
-void WebUILoginView::OnVirtualKeyboardStateChanged(bool activated,
-                                                   aura::Window* root_window) {
-  auto* keyboard_controller = keyboard::KeyboardController::Get();
-  DCHECK(keyboard_controller);
-  if (keyboard_controller->enabled()) {
-    if (activated) {
-      if (!keyboard_controller->HasObserver(this))
-        keyboard_controller->AddObserver(this);
-    } else {
-      keyboard_controller->RemoveObserver(this);
-    }
-  }
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // keyboard::KeyboardControllerObserver:
 

chrome/browser/chromeos/login/ui/webui_login_view.h

@@ -8,7 +8,6 @@
 #include <map>
 #include <string>
 
-#include "ash/shell_observer.h"
 #include "ash/system/system_tray_focus_observer.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
@@ -42,7 +41,6 @@ class OobeUI;
 // View used to render a WebUI supporting Widget. This widget is used for the
 // WebUI based start up and lock screens. It contains a WebView.
 class WebUILoginView : public views::View,
-                       public ash::ShellObserver,
                        public keyboard::KeyboardControllerObserver,
                        public content::WebContentsDelegate,
                        public content::NotificationObserver,
@@ -147,10 +145,6 @@ class WebUILoginView : public views::View,
   // Map type for the accelerator-to-identifier map.
   typedef std::map<ui::Accelerator, std::string> AccelMap;
 
-  // ash::ShellObserver:
-  void OnVirtualKeyboardStateChanged(bool activated,
-                                     aura::Window* root_window) override;
-
   // keyboard::KeyboardControllerObserver:
   void OnKeyboardAvailabilityChanged(bool is_available) override;