chromeos-events: Remove SystemKeyEventListener::ModifierObservers.

There are no ModifierObservers anymore. So remove them.

BUG=none
R=derat@chromium.org

Review URL: https://codereview.chromium.org/191523002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255736 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/chromeos/events/system_key_event_listener.cc

@@ -44,7 +44,6 @@ SystemKeyEventListener* SystemKeyEventListener::GetInstance() {
 SystemKeyEventListener::SystemKeyEventListener()
     : stopped_(false),
       num_lock_mask_(0),
-      pressed_modifiers_(0),
       xkb_event_base_(0) {
   input_method::XKeyboard* xkeyboard =
       input_method::InputMethodManager::Get()->GetXKeyboard();
@@ -87,20 +86,11 @@ void SystemKeyEventListener::AddCapsLockObserver(CapsLockObserver* observer) {
   caps_lock_observers_.AddObserver(observer);
 }
 
-void SystemKeyEventListener::AddModifiersObserver(ModifiersObserver* observer) {
-  modifiers_observers_.AddObserver(observer);
-}
-
 void SystemKeyEventListener::RemoveCapsLockObserver(
     CapsLockObserver* observer) {
   caps_lock_observers_.RemoveObserver(observer);
 }
 
-void SystemKeyEventListener::RemoveModifiersObserver(
-    ModifiersObserver* observer) {
-  modifiers_observers_.RemoveObserver(observer);
-}
-
 base::EventStatus SystemKeyEventListener::WillProcessEvent(
     const base::NativeEvent& event) {
   return ProcessedXEvent(event) ? base::EVENT_HANDLED : base::EVENT_CONTINUE;
@@ -115,12 +105,6 @@ void SystemKeyEventListener::OnCapsLock(bool enabled) {
                     OnCapsLockChange(enabled));
 }
 
-void SystemKeyEventListener::OnModifiers(int state) {
-  FOR_EACH_OBSERVER(ModifiersObserver,
-                    modifiers_observers_,
-                    OnModifiersChange(state));
-}
-
 bool SystemKeyEventListener::ProcessedXEvent(XEvent* xevent) {
   input_method::InputMethodManager* input_method_manager =
       input_method::InputMethodManager::Get();
@@ -141,17 +125,6 @@ bool SystemKeyEventListener::ProcessedXEvent(XEvent* xevent) {
             input_method::kDontChange  /* caps lock */,
             input_method::kDisableLock  /* num lock */);
       }
-      int current_modifiers = 0;
-      if (xkey_event->state.mods & ShiftMask)
-        current_modifiers |= ModifiersObserver::SHIFT_PRESSED;
-      if (xkey_event->state.mods & ControlMask)
-        current_modifiers |= ModifiersObserver::CTRL_PRESSED;
-      if (xkey_event->state.mods & Mod1Mask)
-        current_modifiers |= ModifiersObserver::ALT_PRESSED;
-      if (current_modifiers != pressed_modifiers_) {
-        pressed_modifiers_ = current_modifiers;
-        OnModifiers(pressed_modifiers_);
-      }
       return true;
     }
   }

chrome/browser/chromeos/events/system_key_event_listener.h

@@ -26,26 +26,6 @@ class SystemKeyEventListener : public base::MessageLoopForUI::Observer {
     DISALLOW_COPY_AND_ASSIGN(CapsLockObserver);
   };
 
-  // Observer for modifier keys' state changes.
-  class ModifiersObserver {
-   public:
-    enum {
-      SHIFT_PRESSED = 1,
-      CTRL_PRESSED = 1 << 1,
-      ALT_PRESSED = 1 << 2,
-    };
-
-    // |pressed_modifiers| is a bitmask of SHIFT_PRESSED, CTRL_PRESSED and
-    // ALT_PRESSED.
-    virtual void OnModifiersChange(int pressed_modifiers) = 0;
-
-   protected:
-    ModifiersObserver() {}
-    virtual ~ModifiersObserver() {}
-
-    DISALLOW_COPY_AND_ASSIGN(ModifiersObserver);
-  };
-
   static void Initialize();
   static void Shutdown();
   // GetInstance returns NULL if not initialized or if already shutdown.
@@ -54,9 +34,7 @@ class SystemKeyEventListener : public base::MessageLoopForUI::Observer {
   void Stop();
 
   void AddCapsLockObserver(CapsLockObserver* observer);
-  void AddModifiersObserver(ModifiersObserver* observer);
   void RemoveCapsLockObserver(CapsLockObserver* observer);
-  void RemoveModifiersObserver(ModifiersObserver* observer);
 
  private:
   // Defines the delete on exit Singleton traits we like.  Best to have this
@@ -82,9 +60,7 @@ class SystemKeyEventListener : public base::MessageLoopForUI::Observer {
 
   unsigned int num_lock_mask_;
   bool caps_lock_is_on_;
-  int pressed_modifiers_;
   ObserverList<CapsLockObserver> caps_lock_observers_;
-  ObserverList<ModifiersObserver> modifiers_observers_;
 
   // Base X ID for events from the XKB extension.
   int xkb_event_base_;