Remove FWL globals.

xfa/fwl/core/cfwl_pushbutton.h

Index: xfa/fwl/core/cfwl_pushbutton.h
diff --git a/xfa/fwl/core/cfwl_pushbutton.h b/xfa/fwl/core/cfwl_pushbutton.h
index 8f11660ce968f5c60d3b3769489f04353aa19b10..44106d3c2c8a119423377b23161ba026a4d3334f 100644
--- a/xfa/fwl/core/cfwl_pushbutton.h
+++ b/xfa/fwl/core/cfwl_pushbutton.h
@@ -12,13 +12,14 @@
 
 class CFWL_PushButton : public CFWL_Widget {
  public:
-  CFWL_PushButton();
+  CFWL_PushButton(const IFWL_App*);
   ~CFWL_PushButton() override;
 
   IFWL_PushButton* GetWidget() override;
   const IFWL_PushButton* GetWidget() const override;
 
-  FWL_Error Initialize(const CFWL_WidgetProperties* pProperties = nullptr);
+  void Initialize(const CFWL_WidgetProperties* pProperties);
+
   FWL_Error GetCaption(CFX_WideString& wsCaption);
   FWL_Error SetCaption(const CFX_WideStringC& wsCaption);
   CFX_DIBitmap* GetPicture();