Remove unused code.

xfa/fwl/lightwidget/cfwl_theme.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_LIGHTWIDGET_CFWL_THEME_H_
-#define XFA_FWL_LIGHTWIDGET_CFWL_THEME_H_
-
-#include <memory>
-#include <vector>
-
-#include "core/fxcrt/include/fx_coordinates.h"
-#include "core/fxcrt/include/fx_system.h"
-#include "core/fxge/include/fx_dib.h"
-#include "xfa/fwl/core/ifwl_themeprovider.h"
-
-class CFWL_WidgetTP;
-class IFWL_Widget;
-class CFWL_ThemePart;
-class CFWL_ThemeText;
-
-class CFWL_Theme final : public IFWL_ThemeProvider {
- public:
-  CFWL_Theme();
-  ~CFWL_Theme() override;
-
-  // IFWL_ThemeProvider:
-  bool IsValidWidget(IFWL_Widget* pWidget) override;
-  uint32_t GetThemeID(IFWL_Widget* pWidget) override;
-  uint32_t SetThemeID(IFWL_Widget* pWidget,
-                      uint32_t dwThemeID,
-                      FX_BOOL bChildren = TRUE) override;
-  FWL_Error GetThemeMatrix(IFWL_Widget* pWidget, CFX_Matrix& matrix) override;
-  FWL_Error SetThemeMatrix(IFWL_Widget* pWidget,
-                           const CFX_Matrix& matrix) override;
-  FX_BOOL DrawBackground(CFWL_ThemeBackground* pParams) override;
-  FX_BOOL DrawText(CFWL_ThemeText* pParams) override;
-  void* GetCapacity(CFWL_ThemePart* pThemePart,
-                    CFWL_WidgetCapacity dwCapacity) override;
-  FX_BOOL IsCustomizedLayout(IFWL_Widget* pWidget) override;
-  FWL_Error GetPartRect(CFWL_ThemePart* pThemePart, CFX_RectF& rtPart) override;
-  FX_BOOL IsInPart(CFWL_ThemePart* pThemePart,
-                   FX_FLOAT fx,
-                   FX_FLOAT fy) override;
-  FX_BOOL CalcTextRect(CFWL_ThemeText* pParams, CFX_RectF& rect) override;
-
-  FWL_Error Initialize();
-  FWL_Error Finalize();
-  FWL_Error SetFont(IFWL_Widget* pWidget,
-                    const FX_WCHAR* strFont,
-                    FX_FLOAT fFontSize,
-                    FX_ARGB rgbFont);
-  CFWL_WidgetTP* GetTheme(IFWL_Widget* pWidget);
-
- protected:
-  std::vector<std::unique_ptr<CFWL_WidgetTP>> m_ThemesArray;
-};
-
-#endif  // XFA_FWL_LIGHTWIDGET_CFWL_THEME_H_