Adding tests for USB extension API

chrome/browser/extensions/api/usb/usb_device_resource.cc

 // Copyright (c) 2012 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 "chrome/browser/extensions/api/usb/usb_device_resource.h"
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 139 matching lines @@
 }
 
 }  // namespace
 
 namespace extensions {
 
 UsbDeviceResource::UsbDeviceResource(ApiResourceEventNotifier* notifier,
                                      UsbDevice* device)
     : ApiResource(notifier), device_(device) {}
 
-UsbDeviceResource::~UsbDeviceResource() {}
+UsbDeviceResource::~UsbDeviceResource() {
+  Close();
+}
+
+void UsbDeviceResource::Close() {
+  device_->Close();
+}
 
 void UsbDeviceResource::ControlTransfer(const ControlTransferInfo& transfer) {
   UsbDevice::TransferDirection direction;
   UsbDevice::TransferRequestType request_type;
   UsbDevice::TransferRecipient recipient;
   size_t size;
   scoped_refptr<net::IOBuffer> buffer = CreateBufferForTransfer(transfer);
 
   if (!ConvertDirection(transfer.direction, &direction) ||
       !ConvertRequestType(transfer.request_type, &request_type) ||
@@ skipping 67 matching lines @@
                                          UsbTransferStatus status) {
   if (buffer) {
     base::BinaryValue* const response_buffer =
         base::BinaryValue::CreateWithCopiedBuffer(buffer->data(), length);
     event_notifier()->OnTransferComplete(status,
         ConvertTransferStatusToErrorString(status), response_buffer);
   }
 }
 
 }  // namespace extensions