Convert UtilityProcess to use MojoChild/ShellConnection for the shell handshake.

content/browser/mojo/mojo_child_connection.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 "content/browser/mojo/mojo_child_connection.h"
 
 #include <stdint.h>
 #include <utility>
 
 #include "content/public/common/mojo_shell_connection.h"
@@ skipping 17 matching lines @@
   client.Bind(mojo::InterfacePtrInfo<shell::mojom::ShellClient>(
       std::move(shell_client_pipe), 0u));
   shell::mojom::PIDReceiverRequest pid_receiver_request =
       GetProxy(&pid_receiver_);
 
   shell::Identity target(application_name, shell::mojom::kInheritUserID,
                          instance_id);
   shell::Connector::ConnectParams params(target);
   params.set_client_process_connection(std::move(client),
                                        std::move(pid_receiver_request));
+
+  // In some unit testing scenarios a null connector is passed.
+  if (!connector)
+    return;
+
   connection_ = connector->Connect(&params);
 #if defined(OS_ANDROID)
   service_registry_android_ = ServiceRegistryAndroid::Create(
       connection_->GetInterfaceRegistry(), connection_->GetRemoteInterfaces());
 #endif
 }
 
 MojoChildConnection::~MojoChildConnection() {}
 
 void MojoChildConnection::SetProcessHandle(base::ProcessHandle handle) {
   DCHECK(pid_receiver_.is_bound());
   pid_receiver_->SetPID(base::GetProcId(handle));
   pid_receiver_.reset();
 }
 
 }  // namespace content