Cleanup: Remove unneeded browser_thread.h includes.

chrome/browser/usb/usb_device_handle.h

 // Copyright (c) 2013 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_HANDLE_H_
 #define CHROME_BROWSER_USB_USB_DEVICE_HANDLE_H_
 
 #include <map>
 #include <vector>
 
 #include "base/memory/ref_counted.h"
 #include "base/strings/string16.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
 #include "chrome/browser/usb/usb_interface.h"
-#include "content/public/browser/browser_thread.h"
 #include "net/base/completion_callback.h"
 #include "net/base/io_buffer.h"
 
 struct libusb_device_handle;
 struct libusb_iso_packet_descriptor;
 struct libusb_transfer;
 
 typedef libusb_device_handle* PlatformUsbDeviceHandle;
 typedef libusb_iso_packet_descriptor* PlatformUsbIsoPacketDescriptor;
 typedef libusb_transfer* PlatformUsbTransferHandle;
@@ skipping 150 matching lines @@
   // Retain the UsbContext so that the platform context will not be destroyed
   // before this handle.
   scoped_refptr<UsbContext> context_;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(UsbDeviceHandle);
 };
 
 #endif  // CHROME_BROWSER_USB_USB_DEVICE_HANDLE_H_