Extract a Connector interface from Shell that can be cloned & passed to other threads

mojo/shell/public/cpp/lib/connector_impl.h

+// Copyright 2016 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_SHELL_PUBLIC_CPP_LIB_CONNECTOR_IMPL_H_
+#define MOJO_SHELL_PUBLIC_CPP_LIB_CONNECTOR_IMPL_H_
+
+#include "mojo/shell/public/cpp/connector.h"
+#include "mojo/shell/public/interfaces/shell.mojom.h"
+
+namespace mojo {
+
+class ConnectorImpl : public Connector {
+ public:
+  explicit ConnectorImpl(shell::mojom::ConnectorPtrInfo unbound_state);
+  ~ConnectorImpl();
+
+ private:
+  // Connector:
+  scoped_ptr<Connection> Connect(const std::string& url) override;
+  scoped_ptr<Connection> Connect(ConnectParams* params) override;
+  scoped_ptr<Connector> Clone() override;
+
+  shell::mojom::ConnectorPtrInfo unbound_state_;
+  shell::mojom::ConnectorPtr connector_;
+
+  DISALLOW_COPY_AND_ASSIGN(ConnectorImpl);
+};
+
+}  // namespace mojo
+
+#endif  // MOJO_SHELL_PUBLIC_CPP_LIB_CONNECTOR_IMPL_H_