Convert FWL_ERR into an enum class.

xfa/fwl/lightwidget/cfwl_theme.cpp

Index: xfa/fwl/lightwidget/cfwl_theme.cpp
diff --git a/xfa/fwl/lightwidget/cfwl_theme.cpp b/xfa/fwl/lightwidget/cfwl_theme.cpp
index 65a5aaf6897b5deb6aac081f1d8d5d4637e743a4..594dbd84a48d5fa96b9d28b70ce3065cfb6b6281 100644
--- a/xfa/fwl/lightwidget/cfwl_theme.cpp
+++ b/xfa/fwl/lightwidget/cfwl_theme.cpp
@@ -64,13 +64,13 @@ uint32_t CFWL_Theme::SetThemeID(IFWL_Widget* pWidget,
   return dwID;
 }
 
-FWL_ERR CFWL_Theme::GetThemeMatrix(IFWL_Widget* pWidget, CFX_Matrix& matrix) {
-  return FWL_ERR_Succeeded;
+FWL_Error CFWL_Theme::GetThemeMatrix(IFWL_Widget* pWidget, CFX_Matrix& matrix) {
+  return FWL_Error::Succeeded;
 }
 
-FWL_ERR CFWL_Theme::SetThemeMatrix(IFWL_Widget* pWidget,
-                                   const CFX_Matrix& matrix) {
-  return FWL_ERR_Succeeded;
+FWL_Error CFWL_Theme::SetThemeMatrix(IFWL_Widget* pWidget,
+                                     const CFX_Matrix& matrix) {
+  return FWL_Error::Succeeded;
 }
 
 FX_BOOL CFWL_Theme::DrawBackground(CFWL_ThemeBackground* pParams) {
@@ -90,7 +90,8 @@ FX_BOOL CFWL_Theme::IsCustomizedLayout(IFWL_Widget* pWidget) {
   return GetTheme(pWidget)->IsCustomizedLayout(pWidget);
 }
 
-FWL_ERR CFWL_Theme::GetPartRect(CFWL_ThemePart* pThemePart, CFX_RectF& rtPart) {
+FWL_Error CFWL_Theme::GetPartRect(CFWL_ThemePart* pThemePart,
+                                  CFX_RectF& rtPart) {
   return GetTheme(pThemePart->m_pWidget)->GetPartRect(pThemePart, rtPart);
 }
 
@@ -104,30 +105,30 @@ FX_BOOL CFWL_Theme::CalcTextRect(CFWL_ThemeText* pParams, CFX_RectF& rect) {
   return GetTheme(pParams->m_pWidget)->CalcTextRect(pParams, rect);
 }
 
-FWL_ERR CFWL_Theme::Initialize() {
+FWL_Error CFWL_Theme::Initialize() {
   for (const auto& pTheme : m_ThemesArray)
     pTheme->Initialize();
 
   FWLTHEME_Init();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
-FWL_ERR CFWL_Theme::Finalize() {
+FWL_Error CFWL_Theme::Finalize() {
   for (const auto& pTheme : m_ThemesArray)
     pTheme->Finalize();
 
   FWLTHEME_Release();
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
-FWL_ERR CFWL_Theme::SetFont(IFWL_Widget* pWidget,
-                            const FX_WCHAR* strFont,
-                            FX_FLOAT fFontSize,
-                            FX_ARGB rgbFont) {
+FWL_Error CFWL_Theme::SetFont(IFWL_Widget* pWidget,
+                              const FX_WCHAR* strFont,
+                              FX_FLOAT fFontSize,
+                              FX_ARGB rgbFont) {
   for (const auto& pTheme : m_ThemesArray)
     pTheme->SetFont(pWidget, strFont, fFontSize, rgbFont);
 
-  return FWL_ERR_Succeeded;
+  return FWL_Error::Succeeded;
 }
 
 CFWL_WidgetTP* CFWL_Theme::GetTheme(IFWL_Widget* pWidget) {