Add action for each button on opt-in IME menu.

chrome/browser/chromeos/input_method/input_method_manager_impl.h

Index: chrome/browser/chromeos/input_method/input_method_manager_impl.h
diff --git a/chrome/browser/chromeos/input_method/input_method_manager_impl.h b/chrome/browser/chromeos/input_method/input_method_manager_impl.h
index 46a15012093b60d927088a89f5f02a431c8166a6..25b58cf954f8a61dfb5ab755f056325c5937121d 100644
--- a/chrome/browser/chromeos/input_method/input_method_manager_impl.h
+++ b/chrome/browser/chromeos/input_method/input_method_manager_impl.h
@@ -175,6 +175,8 @@ class InputMethodManagerImpl : public InputMethodManager,
       const std::string& engine_id,
       const std::vector<InputMethodManager::MenuItem>& items) override;
   void MaybeNotifyImeMenuActivationChanged() override;
+  void OverrideKeyboardRef(const std::string& keyset) override;
+  bool IsEmojiHandwritingVoiceOnImeMenuEnabled() override;
 
   // chromeos::UserAddingScreen:
   void OnUserAddingStarted() override;