Adding use_system_libusb option for third_party/libusb

chrome/browser/usb/usb_device.h

 // 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.
 
 #ifndef CHROME_BROWSER_USB_USB_DEVICE_H_
 #define CHROME_BROWSER_USB_USB_DEVICE_H_
 #pragma once
 
 #include <map>
 
 #include "base/memory/ref_counted.h"
 #include "base/synchronization/lock.h"
 #include "net/base/completion_callback.h"
 #include "net/base/io_buffer.h"
-#include "third_party/libusb/libusb/libusb.h"
+#include "third_party/libusb/libusb.h"
 
 typedef libusb_device* PlatformUsbDevice;
 typedef libusb_device_handle* PlatformUsbDeviceHandle;
 typedef libusb_transfer* PlatformUsbTransferHandle;
 
 class UsbService;
 
 namespace net {
 class IOBuffer;
 }  // namespace net
@@ skipping 80 matching lines @@
   // transfers_ tracks all in-flight transfers associated with this device,
   // allowing the device to retain the buffer and callback associated with a
   // transfer until such time that it completes. It is protected by lock_.
   base::Lock lock_;
   std::map<PlatformUsbTransferHandle, Transfer> transfers_;
 
   DISALLOW_EVIL_CONSTRUCTORS(UsbDevice);
 };
 
 #endif  // CHROME_BROWSER_USB_USB_DEVICE_H_