Fix WebView compositor input handling

content/renderer/gpu/input_handler_manager_client.h

+// Copyright (c) 2013 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 CONTENT_RENDERER_GPU_INPUT_HANDLER_MANAGER_CLIENT_H_
+#define CONTENT_RENDERER_GPU_INPUT_HANDLER_MANAGER_CLIENT_H_
+
+#include "base/basictypes.h"
+#include "base/callback_forward.h"
+#include "content/common/content_export.h"
+
+namespace WebKit {
+class WebInputEvent;
+}
+
+namespace content {
+
+class CONTENT_EXPORT InputHandlerManagerClient {
+ public:
+  virtual ~InputHandlerManagerClient() {}
+
+  // The Manager will supply a |handler| when bound to the client. This is valid
+  // until the manager shuts down, at which point it supplies a null |handler|.
+  // The client should only makes calls to |handler| on the compositor thread.
+  typedef base::Callback<InputEventAckState(
+      int /*routing_id*/, const WebKit::WebInputEvent*)> Handler;
+
+  // Called from the main thread.
+  virtual void SetBoundHandler(const Handler& handler) = 0;
+
+  // Called from the compositor thread.
+  virtual void DidAddInputHandler(int routing_id) = 0;
+  virtual void DidRemoveInputHandler(int routing_id) = 0;
+
+ protected:
+  InputHandlerManagerClient() {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(InputHandlerManagerClient);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_GPU_INPUT_HANDLER_MANAGER_CLIENT_H_