exo: Implement support for zcr_keyboard_configuration_v1 protocol.

components/exo/wm_helper.cc

Index: components/exo/wm_helper.cc
diff --git a/components/exo/wm_helper.cc b/components/exo/wm_helper.cc
index 6be7aff4f67848660249a06657e7583510a675df..ce51cbafdac052eba4432db889fd52efdfe5d04e 100644
--- a/components/exo/wm_helper.cc
+++ b/components/exo/wm_helper.cc
@@ -70,6 +70,15 @@ void WMHelper::RemoveAccessibilityObserver(AccessibilityObserver* observer) {
   accessibility_observers_.RemoveObserver(observer);
 }
 
+void WMHelper::AddInputDeviceEventObserver(InputDeviceEventObserver* observer) {
+  input_device_event_observers_.AddObserver(observer);
+}
+
+void WMHelper::RemoveInputDeviceEventObserver(
+    InputDeviceEventObserver* observer) {
+  input_device_event_observers_.RemoveObserver(observer);
+}
+
 void WMHelper::NotifyWindowActivated(aura::Window* gained_active,
                                      aura::Window* lost_active) {
   for (ActivationObserver& observer : activation_observers_)
@@ -107,4 +116,9 @@ void WMHelper::NotifyAccessibilityModeChanged() {
     observer.OnAccessibilityModeChanged();
 }
 
+void WMHelper::NotifyKeyboardDeviceConfigurationChanged() {
+  for (InputDeviceEventObserver& observer : input_device_event_observers_)
+    observer.OnKeyboardDeviceConfigurationChanged();
+}
+
 }  // namespace exo