[Device Service] Move Gamepad Blink headers to be part of the Gamepad client library

ppapi/shared_impl/ppb_gamepad_shared.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 PPAPI_SHARED_IMPL_PPB_GAMEPAD_SHARED_H_
 #define PPAPI_SHARED_IMPL_PPB_GAMEPAD_SHARED_H_
 
 #include <stddef.h>
 
 #include "base/atomicops.h"
 #include "base/strings/string16.h"
 #include "ppapi/c/ppb_gamepad.h"
 #include "ppapi/shared_impl/ppapi_shared_export.h"
 
+namespace device {
+class Gamepads;
+}
+
 namespace ppapi {
 
 // TODO(brettw) when we remove the non-IPC-based gamepad implementation, this
 // code should all move into the GamepadResource.
 
 #pragma pack(push, 4)
 
 struct WebKitGamepadButton {
   bool pressed;
   bool touched;
@@ skipping 87 matching lines @@
   base::subtle::Atomic32 sequence;
   WebKitGamepads buffer;
 };
 
 #pragma pack(pop)
 
 PPAPI_SHARED_EXPORT void ConvertWebKitGamepadData(
     const WebKitGamepads& webkit_data,
     PP_GamepadsSampleData* output_data);
 
+PPAPI_SHARED_EXPORT void ConvertDeviceGamepadData(
+    const device::Gamepads& device_data,
+    PP_GamepadsSampleData* output_data);
+
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_PPB_GAMEPAD_SHARED_H_