Convert FWL_ERR into an enum class.

xfa/fwl/lightwidget/cfwl_pushbutton.h

Index: xfa/fwl/lightwidget/cfwl_pushbutton.h
diff --git a/xfa/fwl/lightwidget/cfwl_pushbutton.h b/xfa/fwl/lightwidget/cfwl_pushbutton.h
index 99b067d2cf98e4eadcc849a8ea819e356d744cdc..5ca3dded3767bcb491c33ac091246b3ccd057eae 100644
--- a/xfa/fwl/lightwidget/cfwl_pushbutton.h
+++ b/xfa/fwl/lightwidget/cfwl_pushbutton.h
@@ -13,11 +13,11 @@
 class CFWL_PushButton : public CFWL_Widget {
  public:
   static CFWL_PushButton* Create();
-  FWL_ERR Initialize(const CFWL_WidgetProperties* pProperties = NULL);
-  FWL_ERR GetCaption(CFX_WideString& wsCaption);
-  FWL_ERR SetCaption(const CFX_WideStringC& wsCaption);
+  FWL_Error Initialize(const CFWL_WidgetProperties* pProperties = NULL);
+  FWL_Error GetCaption(CFX_WideString& wsCaption);
+  FWL_Error SetCaption(const CFX_WideStringC& wsCaption);
   CFX_DIBitmap* GetPicture();
-  FWL_ERR SetPicture(CFX_DIBitmap* pBitmap);
+  FWL_Error SetPicture(CFX_DIBitmap* pBitmap);
   CFWL_PushButton();
   virtual ~CFWL_PushButton();
 
@@ -25,7 +25,7 @@ class CFWL_PushButton : public CFWL_Widget {
   class CFWL_PushButtonDP : public IFWL_PushButtonDP {
    public:
     CFWL_PushButtonDP() : m_pBitmap(NULL) {}
-    FWL_ERR GetCaption(IFWL_Widget* pWidget, CFX_WideString& wsCaption);
+    FWL_Error GetCaption(IFWL_Widget* pWidget, CFX_WideString& wsCaption);
     virtual CFX_DIBitmap* GetPicture(IFWL_Widget* pWidget);
     CFX_WideString m_wsCaption;
     CFX_DIBitmap* m_pBitmap;