Add tests for InputDevice/TouchscreenDevice StructTraits.

ui/events/devices/mojo/input_device_struct_traits.h

 // Copyright 2016 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 UI_EVENTS_DEVICES_MOJO_INPUT_DEVICE_STRUCT_TRAITS_H_
 #define UI_EVENTS_DEVICES_MOJO_INPUT_DEVICE_STRUCT_TRAITS_H_
 
 #include <string>
 
-#include "base/strings/string_piece.h"
 #include "ui/events/devices/input_device.h"
 #include "ui/events/devices/mojo/input_devices.mojom.h"
 #include "ui/events/devices/touchscreen_device.h"
 #include "ui/gfx/geometry/size.h"
 
 namespace mojo {
 
 template <>
 struct EnumTraits<ui::mojom::InputDeviceType, ui::InputDeviceType> {
   static ui::mojom::InputDeviceType ToMojom(ui::InputDeviceType type);
   static bool FromMojom(ui::mojom::InputDeviceType type,
                         ui::InputDeviceType* output);
 };
 
 template <>
 struct StructTraits<ui::mojom::InputDevice, ui::InputDevice> {
   static int32_t id(const ui::InputDevice& device) { return device.id; }
 
   static ui::InputDeviceType type(const ui::InputDevice& device) {
     return device.type;
   }
 
   static const std::string& name(const ui::InputDevice& device) {
     return device.name;
   }
 
-  static base::StringPiece sys_path(const ui::InputDevice& device) {
+  static std::string sys_path(const ui::InputDevice& device) {
     return device.sys_path.AsUTF8Unsafe();
   }
 
   static uint32_t vendor_id(const ui::InputDevice& device) {
     return device.vendor_id;
   }
 
   static uint32_t product_id(const ui::InputDevice& device) {
     return device.product_id;
   }
@@ skipping 16 matching lines @@
     return device.touch_points;
   }
 
   static bool Read(ui::mojom::TouchscreenDeviceDataView data,
                    ui::TouchscreenDevice* out);
 };
 
 }  // namespace mojo
 
 #endif  // UI_EVENTS_DEVICES_MOJO_INPUT_DEVICE_STRUCT_TRAITS_H_