Mojo: Use new message APIs to reduce copying

mojo/public/cpp/bindings/lib/pickle_buffer.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 MOJO_PUBLIC_CPP_BINDINGS_LIB_PICKLE_BUFFER_H_
-#define MOJO_PUBLIC_CPP_BINDINGS_LIB_PICKLE_BUFFER_H_
-
-#include <stddef.h>
-
-#include <memory>
-
-#include "base/macros.h"
-#include "base/pickle.h"
-#include "mojo/public/cpp/bindings/lib/buffer.h"
-
-namespace mojo {
-namespace internal {
-
-// An implementation of Buffer which uses base::Pickle for its backing. Note
-// that this does not use Pickle's header structure at all, instead storing
-// the complete Message (including header) in the Pickle's payload.
-class PickleBuffer : public Buffer {
- public:
-  PickleBuffer(size_t num_bytes, bool zero_initialized);
-  ~PickleBuffer() override;
-
-  const void* data() const;
-
-  void* data() {
-    return const_cast<void*>(static_cast<const PickleBuffer*>(this)->data());
-  }
-
-  size_t data_num_bytes() const;
-
-  base::Pickle* pickle() const;
-
- private:
-  class Storage;
-
-  // Buffer implementation. Note that this cannot grow the Pickle's capacity and
-  // it is an error to Allocate() more bytes in total than have been
-  // pre-allocated using ReserveCapacity() or ReserveUninitializedCapacity().
-  //
-  // This guarantees that the returned data is aligned on an 8-byte boundary.
-  void* Allocate(size_t num_bytes) override;
-  PickleBuffer* AsPickleBuffer() override;
-
-  std::unique_ptr<Storage> storage_;
-
-  DISALLOW_COPY_AND_ASSIGN(PickleBuffer);
-};
-
-}  // namespace internal
-}  // namespace mojo
-
-#endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_PICKLE_BUFFER_H_