Move xfa/fwl/core to xfa/fwl.

xfa/fwl/core/ifwl_themeprovider.h

-// Copyright 2014 PDFium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
-
-#ifndef XFA_FWL_CORE_IFWL_THEMEPROVIDER_H_
-#define XFA_FWL_CORE_IFWL_THEMEPROVIDER_H_
-
-#include "core/fxcrt/fx_coordinates.h"
-#include "xfa/fwl/theme/cfwl_widgettp.h"
-
-class CFWL_ThemeBackground;
-class CFWL_ThemePart;
-class CFWL_ThemeText;
-class CFWL_Widget;
-
-class IFWL_ThemeProvider {
- public:
-  virtual ~IFWL_ThemeProvider() {}
-
-  virtual void DrawBackground(CFWL_ThemeBackground* pParams) = 0;
-  virtual void DrawText(CFWL_ThemeText* pParams) = 0;
-  virtual void* GetCapacity(CFWL_ThemePart* pThemePart,
-                            CFWL_WidgetCapacity dwCapacity) = 0;
-  virtual void CalcTextRect(CFWL_ThemeText* pParams, CFX_RectF& rect) = 0;
-};
-
-#endif  // XFA_FWL_CORE_IFWL_THEMEPROVIDER_H_