Support custom message filtering on Mojo binding objects

mojo/public/cpp/bindings/message_filter.h

Index: mojo/public/cpp/bindings/message_filter.h
diff --git a/mojo/public/cpp/bindings/message_filter.h b/mojo/public/cpp/bindings/message_filter.h
deleted file mode 100644
index 638c53bc82975b37737e88d44b5d5e52375c08dd..0000000000000000000000000000000000000000
--- a/mojo/public/cpp/bindings/message_filter.h
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2014 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 MOJO_PUBLIC_CPP_BINDINGS_MESSAGE_FILTER_H_
-#define MOJO_PUBLIC_CPP_BINDINGS_MESSAGE_FILTER_H_
-
-#include "mojo/public/cpp/bindings/message.h"
-
-namespace mojo {
-
-// This class is the base class for message filters. Subclasses should
-// implement the pure virtual method Accept() inherited from MessageReceiver to
-// process messages and/or forward them to |sink_|.
-class MessageFilter : public MessageReceiver {
- public:
-  // Doesn't take ownership of |sink|. Therefore |sink| has to stay alive while
-  // this object is alive.
-  explicit MessageFilter(MessageReceiver* sink = nullptr);
-  ~MessageFilter() override;
-
-  void set_sink(MessageReceiver* sink) { sink_ = sink; }
-
- protected:
-  MessageReceiver* sink_;
-};
-
-// A trivial filter that simply forwards every message it receives to |sink_|.
-class PassThroughFilter : public MessageFilter {
- public:
-  explicit PassThroughFilter(MessageReceiver* sink = nullptr);
-
-  bool Accept(Message* message) override;
-};
-
-}  // namespace mojo
-
-#endif  // MOJO_PUBLIC_CPP_BINDINGS_MESSAGE_FILTER_H_