Cleanup unused methods and return values in FWL code.

xfa/fwl/core/ifwl_scrollbar.h

Index: xfa/fwl/core/ifwl_scrollbar.h
diff --git a/xfa/fwl/core/ifwl_scrollbar.h b/xfa/fwl/core/ifwl_scrollbar.h
index 39d3c04eb2d22d4d923cb1223eb63fa12a8af60d..95fe7739fea16575ec627379da6477cd56730286 100644
--- a/xfa/fwl/core/ifwl_scrollbar.h
+++ b/xfa/fwl/core/ifwl_scrollbar.h
@@ -18,7 +18,6 @@ class CFWL_ScrollBarImpDelegate;
 class CFWL_WidgetImpProperties;
 class IFWL_Widget;
 
-#define FWL_CLASS_ScrollBar L"FWL_SCROLLBAR"
 #define FWL_STYLEEXT_SCB_Horz (0L << 0)
 #define FWL_STYLEEXT_SCB_Vert (1L << 0)
 
@@ -44,10 +43,9 @@ class IFWL_ScrollBar : public IFWL_Widget, public IFWL_Timer {
   ~IFWL_ScrollBar() override;
 
   // IFWL_Widget
-  FWL_Error GetClassName(CFX_WideString& wsClass) const override;
   FWL_Type GetClassID() const override;
   FWL_Error Initialize() override;
-  FWL_Error Finalize() override;
+  void Finalize() override;
   FWL_Error GetWidgetRect(CFX_RectF& rect, FX_BOOL bAutoSize = FALSE) override;
   FWL_Error Update() override;
   FWL_Error DrawWidget(CFX_Graphics* pGraphics,
@@ -124,7 +122,7 @@ class IFWL_ScrollBar : public IFWL_Widget, public IFWL_Timer {
   CFX_RectF m_rtMaxBtn;
   CFX_RectF m_rtMinTrack;
   CFX_RectF m_rtMaxTrack;
-  FX_BOOL m_bCustomLayout;
+  bool m_bCustomLayout;
   FX_FLOAT m_fMinThumb;
 
  protected: