Implement sync of keyboard layout between Ozone and Wayland clients

ash/system/tray_caps_lock.h

Index: ash/system/tray_caps_lock.h
diff --git a/ash/system/tray_caps_lock.h b/ash/system/tray_caps_lock.h
index 8c86411b585723734f1e50dbcc0d68fe6022a9fe..dbf99959d7b6f7199203fb20af951977bdf59b24 100644
--- a/ash/system/tray_caps_lock.h
+++ b/ash/system/tray_caps_lock.h
@@ -24,8 +24,9 @@ class TrayCapsLock : public TrayImageItem,
   ~TrayCapsLock() override;
 
  private:
-  // Overriden from chromeos::input_method::ImeKeyboard::Observer:
+  // Overridden from chromeos::input_method::ImeKeyboard::Observer:
   void OnCapsLockChanged(bool enabled) override;
+  void OnLayoutChanging(const std::string& layout_name) override {}
 
   // Overridden from TrayImageItem.
   bool GetInitialVisibility() override;