Convert FWL_ERR into an enum class.

xfa/fwl/lightwidget/cfwl_widgetdelegate.cpp

Index: xfa/fwl/lightwidget/cfwl_widgetdelegate.cpp
diff --git a/xfa/fwl/lightwidget/cfwl_widgetdelegate.cpp b/xfa/fwl/lightwidget/cfwl_widgetdelegate.cpp
index 1596aba48a400e4a7373986b1c4d3f8bf520522d..fcb723262208e43fa58bc14e3556dfc4d43e0ca6 100644
--- a/xfa/fwl/lightwidget/cfwl_widgetdelegate.cpp
+++ b/xfa/fwl/lightwidget/cfwl_widgetdelegate.cpp
@@ -13,15 +13,9 @@ CFWL_WidgetDelegate::CFWL_WidgetDelegate() {}
 
 CFWL_WidgetDelegate::~CFWL_WidgetDelegate() {}
 
-int32_t CFWL_WidgetDelegate::OnProcessMessage(CFWL_Message* pMessage) {
-  return 1;
-}
-
-FWL_ERR CFWL_WidgetDelegate::OnProcessEvent(CFWL_Event* pEvent) {
-  return FWL_ERR_Succeeded;
-}
-
-FWL_ERR CFWL_WidgetDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
-                                          const CFX_Matrix* pMatrix) {
-  return FWL_ERR_Succeeded;
-}
+void CFWL_WidgetDelegate::OnProcessMessage(CFWL_Message* pMessage) {}
+
+void CFWL_WidgetDelegate::OnProcessEvent(CFWL_Event* pEvent) {}
+
+void CFWL_WidgetDelegate::OnDrawWidget(CFX_Graphics* pGraphics,
+                                       const CFX_Matrix* pMatrix) {}