Convert FWL_ERR into an enum class.

xfa/fwl/basewidget/fwl_pictureboximp.h

Index: xfa/fwl/basewidget/fwl_pictureboximp.h
diff --git a/xfa/fwl/basewidget/fwl_pictureboximp.h b/xfa/fwl/basewidget/fwl_pictureboximp.h
index f2e67124f63e39e4a580fb7ce54f716833264574..8b0e8d983278b17513828c765f36edf17ea616b5 100644
--- a/xfa/fwl/basewidget/fwl_pictureboximp.h
+++ b/xfa/fwl/basewidget/fwl_pictureboximp.h
@@ -18,14 +18,14 @@ class CFWL_PictureBoxImp : public CFWL_WidgetImp {
   CFWL_PictureBoxImp(const CFWL_WidgetImpProperties& properties,
                      IFWL_Widget* pOuter);
   ~CFWL_PictureBoxImp();
-  virtual FWL_ERR GetClassName(CFX_WideString& wsClass) const;
+  virtual FWL_Error GetClassName(CFX_WideString& wsClass) const;
   virtual uint32_t GetClassID() const;
-  virtual FWL_ERR Initialize();
-  virtual FWL_ERR Finalize();
-  virtual FWL_ERR GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
-  virtual FWL_ERR Update();
-  virtual FWL_ERR DrawWidget(CFX_Graphics* pGraphics,
-                             const CFX_Matrix* pMatrix = NULL);
+  virtual FWL_Error Initialize();
+  virtual FWL_Error Finalize();
+  virtual FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE);
+  virtual FWL_Error Update();
+  virtual FWL_Error DrawWidget(CFX_Graphics* pGraphics,
+                               const CFX_Matrix* pMatrix = NULL);
 
  protected:
   void DrawBkground(CFX_Graphics* pGraphics,
@@ -43,8 +43,8 @@ class CFWL_PictureBoxImp : public CFWL_WidgetImp {
 class CFWL_PictureBoxImpDelegate : public CFWL_WidgetImpDelegate {
  public:
   CFWL_PictureBoxImpDelegate(CFWL_PictureBoxImp* pOwner);
-  FWL_ERR OnDrawWidget(CFX_Graphics* pGraphics,
-                       const CFX_Matrix* pMatrix = NULL) override;
+  FWL_Error OnDrawWidget(CFX_Graphics* pGraphics,
+                         const CFX_Matrix* pMatrix = NULL) override;
 
  protected:
   CFWL_PictureBoxImp* m_pOwner;