* Remove all Preference code from InputMethodMenu. Always handle IME preferences in BrowserStateMonitor and Preferences regardless of the uber tray flag.

* Remove PreferenceObserver from InputMethodManager.
* Use Observer instead of PreferenceObserver in BrowserStateMonitor.

BUG=chromiun-os:28297
TEST=manual

Review URL: https://chromiumcodereview.appspot.com/9838095

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@130564 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 34 insertions, 287 deletions

diff --git a/chrome/browser/chromeos/input_method/browser_state_monitor.cc b/chrome/browser/chromeos/input_method/browser_state_monitor.cc
index cc5636e..c2528f1 100644
--- a/chrome/browser/chromeos/input_method/browser_state_monitor.cc
+++ b/chrome/browser/chromeos/input_method/browser_state_monitor.cc
@@ -4,8 +4,6 @@
 
 #include "chrome/browser/chromeos/input_method/browser_state_monitor.h"
 
-#include "ash/ash_switches.h"
-#include "base/command_line.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/input_method/input_method_util.h"
 #include "chrome/browser/chromeos/language_preferences.h"
@@ -32,13 +30,6 @@ BrowserStateMonitor::BrowserStateMonitor(InputMethodManager* manager)
     : manager_(manager),
       state_(InputMethodManager::STATE_LOGIN_SCREEN),
       initialized_(false) {
-  // On R19, when Uber Tray is disabled, the IME status button will update the
-  // Preferences.
-  // TODO(yusukes): Remove all Preferences code from the button on R20.
-  if (CommandLine::ForCurrentProcess()->HasSwitch(
-          ash::switches::kDisableAshUberTray))
-    return;
-
   notification_registrar_.Add(this,
                               chrome::NOTIFICATION_LOGIN_USER_CHANGED,
                               content::NotificationService::AllSources());
@@ -55,13 +46,11 @@ BrowserStateMonitor::BrowserStateMonitor(InputMethodManager* manager)
                               content::NotificationService::AllSources());
 
   // TODO(yusukes): Tell the initial state to the manager.
-  manager_->AddPreLoginPreferenceObserver(this);
-  manager_->AddPostLoginPreferenceObserver(this);
+  manager_->AddObserver(this);
 }
 
 BrowserStateMonitor::~BrowserStateMonitor() {
-  manager_->RemovePostLoginPreferenceObserver(this);
-  manager_->RemovePreLoginPreferenceObserver(this);
+  manager_->RemoveObserver(this);
 }
 
 void BrowserStateMonitor::UpdateLocalState(
@@ -91,10 +80,10 @@ void BrowserStateMonitor::UpdateUserPreferences(
   current_input_method_pref_.SetValue(current_input_method);
 }
 
-void BrowserStateMonitor::PreferenceUpdateNeeded(
-    input_method::InputMethodManager* manager,
-    const input_method::InputMethodDescriptor& previous_input_method,
-    const input_method::InputMethodDescriptor& current_input_method) {
+void BrowserStateMonitor::InputMethodChanged(
+    InputMethodManager* manager,
+    const InputMethodDescriptor& current_input_method,
+    size_t num_active_input_methods) {
   DCHECK_EQ(manager_, manager);
   // Save the new input method id depending on the current browser state.
   switch (state_) {
diff --git a/chrome/browser/chromeos/input_method/browser_state_monitor.h b/chrome/browser/chromeos/input_method/browser_state_monitor.h
index bd7f01b..4512b98 100644
--- a/chrome/browser/chromeos/input_method/browser_state_monitor.h
+++ b/chrome/browser/chromeos/input_method/browser_state_monitor.h
@@ -24,7 +24,7 @@ namespace input_method {
 // state.
 class BrowserStateMonitor
     : public content::NotificationObserver,
-      public input_method::InputMethodManager::PreferenceObserver {
+      public input_method::InputMethodManager::Observer {
  public:
   explicit BrowserStateMonitor(InputMethodManager* manager);
   virtual ~BrowserStateMonitor();
@@ -36,15 +36,18 @@ class BrowserStateMonitor
   virtual void UpdateUserPreferences(const std::string& current_input_method);
 
  private:
-  // InputMethodManager::PreferenceObserver implementation.
-  // TODO(yusukes): On R20, use input_method::InputMethodManager::Observer and
-  // remove the PreferenceObserver interface from InputMethodManager.
-  virtual void PreferenceUpdateNeeded(
-      input_method::InputMethodManager* manager,
-      const input_method::InputMethodDescriptor& previous_input_method,
-      const input_method::InputMethodDescriptor& current_input_method) OVERRIDE;
-  virtual void FirstObserverIsAdded(
-      input_method::InputMethodManager* manager) OVERRIDE {}
+  // InputMethodManager::Observer implementation.
+  virtual void InputMethodChanged(
+      InputMethodManager* manager,
+      const InputMethodDescriptor& current_input_method,
+      size_t num_active_input_methods) OVERRIDE;
+  virtual void ActiveInputMethodsChanged(
+      InputMethodManager* manager,
+      const InputMethodDescriptor& current_input_method,
+      size_t num_active_input_methods) OVERRIDE {}
+  virtual void PropertyListChanged(
+      InputMethodManager* manager,
+      const InputMethodPropertyList& current_ime_properties) OVERRIDE {}
 
   // content::NotificationObserver overrides:
   virtual void Observe(int type,
diff --git a/chrome/browser/chromeos/input_method/input_method_manager.cc b/chrome/browser/chromeos/input_method/input_method_manager.cc
index 9887c49..7b0f302 100644
--- a/chrome/browser/chromeos/input_method/input_method_manager.cc
+++ b/chrome/browser/chromeos/input_method/input_method_manager.cc
@@ -132,32 +132,6 @@ class InputMethodManagerImpl : public InputMethodManager,
     candidate_window_observers_.RemoveObserver(observer);
   }
 
-  virtual void AddPreLoginPreferenceObserver(
-      InputMethodManager::PreferenceObserver* observer) {
-    if (!pre_login_preference_observers_.size()) {
-      observer->FirstObserverIsAdded(this);
-    }
-    pre_login_preference_observers_.AddObserver(observer);
-  }
-
-  virtual void RemovePreLoginPreferenceObserver(
-      InputMethodManager::PreferenceObserver* observer) {
-    pre_login_preference_observers_.RemoveObserver(observer);
-  }
-
-  virtual void AddPostLoginPreferenceObserver(
-      InputMethodManager::PreferenceObserver* observer) {
-    if (!post_login_preference_observers_.size()) {
-      observer->FirstObserverIsAdded(this);
-    }
-    post_login_preference_observers_.AddObserver(observer);
-  }
-
-  virtual void RemovePostLoginPreferenceObserver(
-      InputMethodManager::PreferenceObserver* observer) {
-    post_login_preference_observers_.RemoveObserver(observer);
-  }
-
   virtual void AddVirtualKeyboardObserver(VirtualKeyboardObserver* observer) {
     virtual_keyboard_observers_.AddObserver(observer);
   }
@@ -910,23 +884,6 @@ class InputMethodManagerImpl : public InputMethodManager,
     }
   }
 
-  // Ask the first observer to update preferences. We should not ask every
-  // observer to do so. Otherwise, we'll end up updating preferences many times
-  // when many observers are attached (ex. many windows are opened), which is
-  // unnecessary and expensive.
-  bool UpdateInputMethodPreference(
-      ObserverList<PreferenceObserver>* observers) {
-    ObserverListBase<PreferenceObserver>::Iterator it(*observers);
-    PreferenceObserver* first_observer = it.GetNext();
-    if (!first_observer) {
-      return false;
-    }
-    first_observer->PreferenceUpdateNeeded(this,
-                                           previous_input_method_,
-                                           current_input_method_);
-    return true;
-  }
-
   // Changes the current input method from the given input method
   // descriptor.  This function updates states like current_input_method_
   // and notifies observers about the change (that will update the
@@ -943,13 +900,6 @@ class InputMethodManagerImpl : public InputMethodManager,
         LOG(ERROR) << "Failed to change keyboard layout to "
                    << current_input_method_.keyboard_layout();
       }
-
-      // Save the input method names to the Pref.
-      if (!UpdateInputMethodPreference(&post_login_preference_observers_)) {
-        // When both pre- and post-login observers are available, only notifies
-        // the latter one.
-        UpdateInputMethodPreference(&pre_login_preference_observers_);
-      }
     }
 
     // Update input method indicators (e.g. "US", "DV") in Chrome windows.
@@ -1226,8 +1176,6 @@ class InputMethodManagerImpl : public InputMethodManager,
   ObserverList<InputMethodManager::Observer> observers_;
   ObserverList<InputMethodManager::CandidateWindowObserver>
       candidate_window_observers_;
-  ObserverList<PreferenceObserver> pre_login_preference_observers_;
-  ObserverList<PreferenceObserver> post_login_preference_observers_;
   ObserverList<VirtualKeyboardObserver> virtual_keyboard_observers_;
 
   // The input method which was/is selected.
diff --git a/chrome/browser/chromeos/input_method/input_method_manager.h b/chrome/browser/chromeos/input_method/input_method_manager.h
index d12d3d6d..b9367f7 100644
--- a/chrome/browser/chromeos/input_method/input_method_manager.h
+++ b/chrome/browser/chromeos/input_method/input_method_manager.h
@@ -60,12 +60,14 @@ class InputMethodManager {
         size_t num_active_input_methods) = 0;
 
     // Called when the active input methods are changed.
+    // TODO(yusukes): Remove this method in R20.
     virtual void ActiveInputMethodsChanged(
         InputMethodManager* manager,
         const InputMethodDescriptor& current_input_method,
         size_t num_active_input_methods) = 0;
 
     // Called when the list of properties is changed.
+    // TODO(yusukes): Remove this method in R20.
     virtual void PropertyListChanged(
         InputMethodManager* manager,
         const InputMethodPropertyList& current_ime_properties) = 0;
@@ -87,20 +89,6 @@ class InputMethodManager {
     virtual void CandidateWindowClosed(InputMethodManager* manager) = 0;
   };
 
-  class PreferenceObserver {
-   public:
-    virtual ~PreferenceObserver() {}
-
-    // Called when the preferences have to be updated.
-    virtual void PreferenceUpdateNeeded(
-        InputMethodManager* manager,
-        const InputMethodDescriptor& previous_input_method,
-        const InputMethodDescriptor& current_input_method) = 0;
-
-    // Called by AddObserver() when the first observer is added.
-    virtual void FirstObserverIsAdded(InputMethodManager* obj) = 0;
-  };
-
   class VirtualKeyboardObserver {
    public:
     virtual ~VirtualKeyboardObserver() {}
@@ -120,17 +108,11 @@ class InputMethodManager {
   virtual void AddObserver(Observer* observer) = 0;
   virtual void AddCandidateWindowObserver(
       CandidateWindowObserver* observer) = 0;
-  virtual void AddPreLoginPreferenceObserver(PreferenceObserver* observer) = 0;
-  virtual void AddPostLoginPreferenceObserver(PreferenceObserver* observer) = 0;
   virtual void AddVirtualKeyboardObserver(
       VirtualKeyboardObserver* observer) = 0;
   virtual void RemoveObserver(Observer* observer) = 0;
   virtual void RemoveCandidateWindowObserver(
       CandidateWindowObserver* observer) = 0;
-  virtual void RemovePreLoginPreferenceObserver(
-      PreferenceObserver* observer) = 0;
-  virtual void RemovePostLoginPreferenceObserver(
-      PreferenceObserver* observer) = 0;
   virtual void RemoveVirtualKeyboardObserver(
       VirtualKeyboardObserver* observer) = 0;
 
diff --git a/chrome/browser/chromeos/preferences.cc b/chrome/browser/chromeos/preferences.cc
index ede7d19..30509bc 100644
--- a/chrome/browser/chromeos/preferences.cc
+++ b/chrome/browser/chromeos/preferences.cc
@@ -4,7 +4,6 @@
 
 #include "chrome/browser/chromeos/preferences.h"
 
-#include "ash/ash_switches.h"
 #include "base/chromeos/chromeos_version.h"
 #include "base/command_line.h"
 #include "base/i18n/time_formatting.h"
@@ -446,8 +445,7 @@ void Preferences::NotifyPrefChanged(const std::string* pref_name) {
   // Do not check |*pref_name| for the two prefs. We're only interested in
   // initial values of the prefs.
   // TODO(yusukes): Remove the second condition on R20.
-  if (!pref_name && !CommandLine::ForCurrentProcess()->HasSwitch(
-          ash::switches::kDisableAshUberTray)) {
+  if (!pref_name) {
     const std::string previous_input_method_id =
         previous_input_method_.GetValue();
     const std::string current_input_method_id =
diff --git a/chrome/browser/chromeos/status/input_method_menu.cc b/chrome/browser/chromeos/status/input_method_menu.cc
index f27db8c..886458c 100644
--- a/chrome/browser/chromeos/status/input_method_menu.cc
+++ b/chrome/browser/chromeos/status/input_method_menu.cc
@@ -13,14 +13,7 @@
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/input_method/input_method_util.h"
-#include "chrome/browser/chromeos/language_preferences.h"
 #include "chrome/browser/chromeos/status/status_area_view_chromeos.h"
-#include "chrome/browser/prefs/pref_service.h"
-#include "chrome/browser/prefs/pref_service.h"
-#include "chrome/browser/profiles/profile_manager.h"
-#include "chrome/common/chrome_notification_types.h"
-#include "chrome/common/pref_names.h"
-#include "content/public/browser/notification_service.h"
 #include "content/public/browser/user_metrics.h"
 #include "grit/generated_resources.h"
 #include "grit/theme_resources.h"
@@ -91,13 +84,6 @@ string16 GetLanguageName(const std::string& language_code) {
   return language_name;
 }
 
-PrefService* GetPrefService() {
-  Profile* profile = ProfileManager::GetDefaultProfile();
-  if (profile)
-    return profile->GetPrefs();
-  return NULL;
-}
-
 }  // namespace
 
 namespace chromeos {
@@ -108,10 +94,8 @@ using input_method::InputMethodManager;
 // InputMethodMenu
 
 InputMethodMenu::InputMethodMenu()
-    : initialized_prefs_(false),
-      initialized_observers_(false),
-      input_method_descriptors_(InputMethodManager::GetInstance()->
-                                GetActiveInputMethods()),
+    : input_method_descriptors_(
+        InputMethodManager::GetInstance()->GetActiveInputMethods()),
       model_(new ui::SimpleMenuModel(NULL)),
       ALLOW_THIS_IN_INITIALIZER_LIST(input_method_menu_delegate_(
           new views::MenuModelAdapter(this))),
@@ -122,33 +106,13 @@ InputMethodMenu::InputMethodMenu()
       menu_alignment_(views::MenuItemView::TOPRIGHT) {
   DCHECK(input_method_descriptors_.get() &&
          !input_method_descriptors_->empty());
-
-  // Sync current and previous input methods on Chrome prefs with ibus-daemon.
-  if (StatusAreaViewChromeos::IsBrowserMode())
-    InitializePrefMembers();
-
-  if (StatusAreaViewChromeos::IsLoginMode()) {
-    registrar_.Add(this,
-                   chrome::NOTIFICATION_LOGIN_USER_CHANGED,
-                   content::NotificationService::AllSources());
-    // On Aura status area is not recreated on sign in. Instead, 2 notifications
-    // are sent to Chrome on sign in: NOTIFICATION_LOGIN_USER_CHANGED with
-    // StatusAreaViewChromeos::IsLoginMode() and NOTIFICATION_SESSION_STARTED
-    // with StatusAreaViewChromeos::IsBrowserMode().
-    // In case of Chrome crash, Chrome will be reloaded but IsLoginMode() will
-    // return false at this point so NOTIFICATION_SESSION_STARTED will be
-    // ignored and all initialization will happen in ctor.
-    registrar_.Add(this,
-                   chrome::NOTIFICATION_SESSION_STARTED,
-                   content::NotificationService::AllSources());
-  }
-  AddObservers();
+  AddObserver();
 }
 
 InputMethodMenu::~InputMethodMenu() {
-  // RemoveObservers() is no-op if |this| object is already removed from the
+  // RemoveObserver() is no-op if |this| object is already removed from the
   // observer list
-  RemoveObservers();
+  RemoveObserver();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -177,7 +141,7 @@ bool InputMethodMenu::IsItemCheckedAt(int index) const {
     const input_method::InputMethodDescriptor& input_method
         = input_method_descriptors_->at(index);
     return input_method == InputMethodManager::GetInstance()->
-          GetCurrentInputMethod();
+        GetCurrentInputMethod();
   }
 
   if (GetPropertyIndex(index, &index)) {
@@ -380,25 +344,6 @@ void InputMethodMenu::InputMethodChanged(
   UpdateUIFromInputMethod(current_input_method, num_active_input_methods);
 }
 
-// TODO(yusukes): Move code for handling preferences to chromeos/input_method/.
-void InputMethodMenu::PreferenceUpdateNeeded(
-    InputMethodManager* manager,
-    const input_method::InputMethodDescriptor& previous_input_method,
-    const input_method::InputMethodDescriptor& current_input_method) {
-  if (StatusAreaViewChromeos::IsBrowserMode()) {
-    if (initialized_prefs_) {  // make sure we're not in unit tests.
-      // Sometimes (e.g. initial boot) |previous_input_method.id()| is empty.
-      previous_input_method_pref_.SetValue(previous_input_method.id());
-      current_input_method_pref_.SetValue(current_input_method.id());
-    }
-  } else if (StatusAreaViewChromeos::IsLoginMode()) {
-    if (g_browser_process && g_browser_process->local_state()) {
-      g_browser_process->local_state()->SetString(
-          language_prefs::kPreferredKeyboardLayout, current_input_method.id());
-    }
-  }
-}
-
 void InputMethodMenu::PropertyListChanged(
     InputMethodManager* manager,
     const input_method::InputMethodPropertyList& current_ime_properties) {
@@ -422,29 +367,6 @@ void InputMethodMenu::PropertyListChanged(
   }
 }
 
-void InputMethodMenu::FirstObserverIsAdded(InputMethodManager* manager) {
-  // NOTICE: Since this function might be called from the constructor of this
-  // class, it's better to avoid calling virtual functions.
-
-  if (initialized_prefs_ && StatusAreaViewChromeos::IsBrowserMode()) {
-    // Get the input method name in the Preferences file which was in use last
-    // time, and switch to the method. We remember two input method names in the
-    // preference so that the Control+space hot-key could work fine from the
-    // beginning. InputMethodChanged() will be called soon and the indicator
-    // will be updated.
-    const std::string previous_input_method_id =
-        previous_input_method_pref_.GetValue();
-    if (!previous_input_method_id.empty()) {
-      manager->ChangeInputMethod(previous_input_method_id);
-    }
-    const std::string current_input_method_id =
-        current_input_method_pref_.GetValue();
-    if (!current_input_method_id.empty()) {
-      manager->ChangeInputMethod(current_input_method_id);
-    }
-  }
-}
-
 void InputMethodMenu::PrepareForMenuOpen() {
   content::RecordAction(UserMetricsAction("LanguageMenuButton_Open"));
   PrepareMenuModel();
@@ -597,80 +519,19 @@ string16 InputMethodMenu::GetTextForMenu(
   return text;
 }
 
-void InputMethodMenu::RegisterPrefs(PrefService* local_state) {
-  // We use an empty string here rather than a hardware keyboard layout name
-  // since input_method::GetHardwareInputMethodId() might return a fallback
-  // layout name if local_state->RegisterStringPref(kHardwareKeyboardLayout)
-  // is not called yet.
-  local_state->RegisterStringPref(language_prefs::kPreferredKeyboardLayout,
-                                  "",
-                                  PrefService::UNSYNCABLE_PREF);
-}
-
-void InputMethodMenu::Observe(int type,
-                              const content::NotificationSource& source,
-                              const content::NotificationDetails& details) {
-  if (type == chrome::NOTIFICATION_LOGIN_USER_CHANGED) {
-    // When a user logs in, we should remove |this| object from the observer
-    // list so that PreferenceUpdateNeeded() does not update the local state
-    // anymore.
-    RemoveObservers();
-  }
-  if (type == chrome::NOTIFICATION_SESSION_STARTED) {
-    InitializePrefMembers();
-    AddObservers();
-    InputMethodManager* manager = InputMethodManager::GetInstance();
-    UpdateUIFromInputMethod(manager->GetCurrentInputMethod(),
-                            manager->GetNumActiveInputMethods());
-  }
-}
-
 void InputMethodMenu::SetMinimumWidth(int width) {
   // On the OOBE network selection screen, fixed width menu would be preferable.
   minimum_input_method_menu_width_ = width;
 }
 
-void InputMethodMenu::AddObservers() {
-  if (initialized_observers_)
-    return;
+void InputMethodMenu::AddObserver() {
   InputMethodManager* manager = InputMethodManager::GetInstance();
-  if (StatusAreaViewChromeos::IsLoginMode()) {
-    manager->AddPreLoginPreferenceObserver(this);
-  } else if (StatusAreaViewChromeos::IsBrowserMode()) {
-    manager->AddPostLoginPreferenceObserver(this);
-  }
-  // AddObserver() should be called after AddXXXLoginPreferenceObserver. This is
-  // because when the function is called FirstObserverIsAdded might be called
-  // back, and FirstObserverIsAdded might then might call ChangeInputMethod() in
-  // InputMethodManager. We have to prevent the manager function from calling
-  // callback functions like InputMethodChanged since they touch (yet
-  // uninitialized) UI elements.
   manager->AddObserver(this);
-  initialized_observers_ = true;
 }
 
-void InputMethodMenu::RemoveObservers() {
+void InputMethodMenu::RemoveObserver() {
   InputMethodManager* manager = InputMethodManager::GetInstance();
-  if (StatusAreaViewChromeos::IsLoginMode()) {
-    manager->RemovePreLoginPreferenceObserver(this);
-  } else if (StatusAreaViewChromeos::IsBrowserMode()) {
-    manager->RemovePostLoginPreferenceObserver(this);
-  }
   manager->RemoveObserver(this);
-  initialized_observers_ = false;
-}
-
-void InputMethodMenu::InitializePrefMembers() {
-  if (!initialized_prefs_) {
-    PrefService* pref_service = GetPrefService();
-    if (pref_service) {
-      initialized_prefs_ = true;
-      previous_input_method_pref_.Init(
-          prefs::kLanguagePreviousInputMethod, pref_service, this);
-      current_input_method_pref_.Init(
-          prefs::kLanguageCurrentInputMethod, pref_service, this);
-    }
-  }
 }
 
 }  // namespace chromeos
diff --git a/chrome/browser/chromeos/status/input_method_menu.h b/chrome/browser/chromeos/status/input_method_menu.h
index 93c789b..3658a20 100644
--- a/chrome/browser/chromeos/status/input_method_menu.h
+++ b/chrome/browser/chromeos/status/input_method_menu.h
@@ -10,10 +10,6 @@
 
 #include "base/compiler_specific.h"
 #include "chrome/browser/chromeos/input_method/input_method_manager.h"
-#include "chrome/browser/prefs/pref_member.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-#include "content/public/browser/notification_types.h"
 #include "ui/base/models/menu_model.h"
 #include "ui/views/controls/button/menu_button_listener.h"
 #include "ui/views/controls/menu/menu_item_view.h"
@@ -40,9 +36,7 @@ namespace chromeos {
 class InputMethodMenu
     : public views::MenuButtonListener,
       public ui::MenuModel,
-      public input_method::InputMethodManager::Observer,
-      public input_method::InputMethodManager::PreferenceObserver,
-      public content::NotificationObserver {
+      public input_method::InputMethodManager::Observer {
  public:
   InputMethodMenu();
   virtual ~InputMethodMenu();
@@ -85,19 +79,6 @@ class InputMethodMenu
       input_method::InputMethodManager* manager,
       const input_method::InputMethodPropertyList& properties) OVERRIDE;
 
-  // InputMethodManager::PreferenceObserver implementation.
-  virtual void PreferenceUpdateNeeded(
-      input_method::InputMethodManager* manager,
-      const input_method::InputMethodDescriptor& previous_input_method,
-      const input_method::InputMethodDescriptor& current_input_method) OVERRIDE;
-  virtual void FirstObserverIsAdded(
-      input_method::InputMethodManager* manager) OVERRIDE;
-
-  // content::NotificationObserver implementation.
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
-
   // Specify menu alignment (default TOPRIGHT).
   void set_menu_alignment(views::MenuItemView::AnchorPosition menu_alignment) {
     menu_alignment_ = menu_alignment;
@@ -109,9 +90,6 @@ class InputMethodMenu
   // Rebuilds menu model.
   void PrepareMenuModel();
 
-  // Registers input method preferences for the login screen.
-  static void RegisterPrefs(PrefService* local_state);
-
   // Returns a string for the drop-down menu and the tooltip for the indicator.
   // The method is public for unit tests.
   static string16 GetTextForMenu(
@@ -160,23 +138,13 @@ class InputMethodMenu
   // item.
   bool IndexPointsToConfigureImeMenuItem(int index) const;
 
-  // Add / Remove InputMethodManager observers.
-  void AddObservers();
-  void RemoveObservers();
-
-  // Initializes objects for reading/writing Chrome prefs.
-  void InitializePrefMembers();
-
-  bool initialized_prefs_;
-  bool initialized_observers_;
+  // Add / Remove InputMethodManager observer.
+  void AddObserver();
+  void RemoveObserver();
 
   // The current input method list.
   scoped_ptr<input_method::InputMethodDescriptors> input_method_descriptors_;
 
-  // Objects for reading/writing the Chrome prefs.
-  StringPrefMember previous_input_method_pref_;
-  StringPrefMember current_input_method_pref_;
-
   // We borrow ui::SimpleMenuModel implementation to maintain the current
   // content of the pop-up menu. The ui::MenuModel is implemented using this
   // |model_|.  The MenuModelAdapter wraps the model with the
@@ -191,8 +159,6 @@ class InputMethodMenu
   // Menu alignment (default TOPRIGHT).
   views::MenuItemView::AnchorPosition menu_alignment_;
 
-  content::NotificationRegistrar registrar_;
-
   DISALLOW_COPY_AND_ASSIGN(InputMethodMenu);
 };