Manage UsbService lifetime in DeviceClient implementations.

device/test/test_device_client.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 "device/test/test_device_client.h"
+
+#include "device/hid/hid_service.h"
+#include "device/usb/usb_service.h"
+
+namespace device {
+
+TestDeviceClient::TestDeviceClient(
+    scoped_refptr<base::SingleThreadTaskRunner> blocking_task_runner)
+    : blocking_task_runner_(blocking_task_runner) {}
+
+TestDeviceClient::~TestDeviceClient() {}
+
+HidService* TestDeviceClient::GetHidService() {
+#if !defined(OS_LINUX) || defined(USE_UDEV)
+  return HidService::GetInstance(blocking_task_runner_);
+#else
+  return nullptr;
+#endif
+}
+
+UsbService* TestDeviceClient::GetUsbService() {
+#if !defined(OS_ANDROID) && !defined(OS_IOS)
+  if (!usb_service_) {
+    usb_service_ = UsbService::Create(blocking_task_runner_);
+  }
+#endif
+  return usb_service_.get();
+}
+
+}  // namespace device