Extract //device/usb mocks so that they can be shared.

device/usb/mock_usb_device.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/usb/mock_usb_device.h"
+
+#include "base/strings/utf_string_conversions.h"
+
+namespace device {
+
+namespace {
+
+static uint32 next_id;
+
+}  // namespace
+
+MockUsbDevice::MockUsbDevice(uint16 vendor_id, uint16 product_id)
+    : UsbDevice(vendor_id,
+                product_id,
+                next_id++,
+                base::string16(),
+                base::string16(),
+                base::string16()) {
+}
+
+MockUsbDevice::MockUsbDevice(uint16 vendor_id,
+                             uint16 product_id,
+                             const std::string& manufacturer_string,
+                             const std::string& product_string,
+                             const std::string& serial_number)
+    : UsbDevice(vendor_id,
+                product_id,
+                next_id++,
+                base::UTF8ToUTF16(manufacturer_string),
+                base::UTF8ToUTF16(product_string),
+                base::UTF8ToUTF16(serial_number)) {
+}
+
+MockUsbDevice::~MockUsbDevice() {
+}
+
+}  // namespace device