Mojo C++ bindings: support disconnect with a reason.

mojo/public/cpp/bindings/lib/control_message_proxy.cc

 // 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.
 
 #include "mojo/public/cpp/bindings/lib/control_message_proxy.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <utility>
 
@@ skipping 145 matching lines @@
   run_loop_quit_closure_ = run_loop.QuitClosure();
   SendRunMessage(
       receiver_, std::move(input_ptr),
       base::Bind(&RunClosure,
                  base::Bind(&ControlMessageProxy::RunFlushForTestingClosure,
                             base::Unretained(this))),
       &context_);
   run_loop.Run();
 }
 
+void ControlMessageProxy::SendDisconnectReason(uint32_t custom_reason,
+                                               const std::string& description) {
+  auto send_disconnect_reason = interface_control::SendDisconnectReason::New();
+  send_disconnect_reason->custom_reason = custom_reason;
+  send_disconnect_reason->description = description;
+  auto input_ptr = interface_control::RunOrClosePipeInput::New();
+  input_ptr->set_send_disconnect_reason(std::move(send_disconnect_reason));
+  SendRunOrClosePipeMessage(receiver_, std::move(input_ptr), &context_);
+}
+
 void ControlMessageProxy::RunFlushForTestingClosure() {
   DCHECK(!run_loop_quit_closure_.is_null());
   base::ResetAndReturn(&run_loop_quit_closure_).Run();
 }
 
 void ControlMessageProxy::OnConnectionError() {
   encountered_error_ = true;
   if (!run_loop_quit_closure_.is_null())
     RunFlushForTestingClosure();
 }
 
 }  // namespace internal
 }  // namespace mojo