mus: Remove the old client lib.

services/ui/public/cpp/input_event_handler.h

-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef SERVICES_UI_PUBLIC_CPP_INPUT_EVENT_HANDLER_H_
-#define SERVICES_UI_PUBLIC_CPP_INPUT_EVENT_HANDLER_H_
-
-#include <memory>
-
-#include "base/callback_forward.h"
-
-namespace ui {
-class Event;
-}
-
-namespace ui {
-
-class Window;
-
-namespace mojom {
-enum class EventResult;
-}
-
-// Responsible for processing input events for ui::Window.
-class InputEventHandler {
- public:
-  // The event handler can asynchronously ack the event by taking ownership of
-  // the |ack_callback|. The callback takes an EventResult indicating if the
-  // handler has consumed the event. If the handler does not take ownership of
-  // the callback, then WindowTreeClient will ack the event as not consumed.
-  virtual void OnWindowInputEvent(
-      Window* target,
-      const ui::Event& event,
-      std::unique_ptr<base::Callback<void(mojom::EventResult)>>*
-          ack_callback) = 0;
-
- protected:
-  virtual ~InputEventHandler() {}
-};
-
-}  // namespace ui
-
-#endif  // SERVICES_UI_PUBLIC_CPP_INPUT_EVENT_HANDLER_H_