Make the fuchsia mojo/public repo the source of truth.

mojo/public/cpp/bindings/lib/shared_data.h

-// 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_LIB_SHARED_DATA_H_
-#define MOJO_PUBLIC_CPP_BINDINGS_LIB_SHARED_DATA_H_
-
-#include "mojo/public/cpp/system/macros.h"
-
-namespace mojo {
-namespace internal {
-
-// Used to allocate an instance of T that can be shared via reference counting.
-template <typename T>
-class SharedData {
- public:
-  ~SharedData() { holder_->Release(); }
-
-  SharedData() : holder_(new Holder()) {}
-
-  explicit SharedData(const T& value) : holder_(new Holder(value)) {}
-
-  SharedData(const SharedData<T>& other) : holder_(other.holder_) {
-    holder_->Retain();
-  }
-
-  SharedData<T>& operator=(const SharedData<T>& other) {
-    if (other.holder_ == holder_)
-      return *this;
-    holder_->Release();
-    holder_ = other.holder_;
-    holder_->Retain();
-    return *this;
-  }
-
-  void reset() {
-    holder_->Release();
-    holder_ = new Holder();
-  }
-
-  void reset(const T& value) {
-    holder_->Release();
-    holder_ = new Holder(value);
-  }
-
-  void set_value(const T& value) { holder_->value = value; }
-  T* mutable_value() { return &holder_->value; }
-  const T& value() const { return holder_->value; }
-
- private:
-  class Holder {
-   public:
-    Holder() : value(), ref_count_(1) {}
-    Holder(const T& value) : value(value), ref_count_(1) {}
-
-    void Retain() { ++ref_count_; }
-    void Release() {
-      if (--ref_count_ == 0)
-        delete this;
-    }
-
-    T value;
-
-   private:
-    int ref_count_;
-    MOJO_DISALLOW_COPY_AND_ASSIGN(Holder);
-  };
-
-  Holder* holder_;
-};
-
-}  // namespace internal
-}  // namespace mojo
-
-#endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_SHARED_DATA_H_