Cleanup CFWL_Widget code to return CFX_RectFs where appropriate

xfa/fwl/cfwl_form.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef XFA_FWL_CFWL_FORM_H_
 #define XFA_FWL_CFWL_FORM_H_
 
 #include <memory>
@@ skipping 25 matching lines @@
 class CFWL_Form : public CFWL_Widget {
  public:
   CFWL_Form(const CFWL_App* app,
             std::unique_ptr<CFWL_WidgetProperties> properties,
             CFWL_Widget* pOuter);
   ~CFWL_Form() override;
 
   // CFWL_Widget
   FWL_Type GetClassID() const override;
   bool IsInstance(const CFX_WideStringC& wsClass) const override;
-  void GetClientRect(CFX_RectF& rect) override;
+  CFX_RectF GetClientRect() override;
   void Update() override;
   FWL_WidgetHit HitTest(FX_FLOAT fx, FX_FLOAT fy) override;
   void DrawWidget(CFX_Graphics* pGraphics, const CFX_Matrix* pMatrix) override;
   void OnProcessMessage(CFWL_Message* pMessage) override;
   void OnDrawWidget(CFX_Graphics* pGraphics,
                     const CFX_Matrix* pMatrix) override;
 
   CFWL_Widget* DoModal();
   void EndDoModal();
 
@@ skipping 33 matching lines @@
   FX_FLOAT m_fCYBorder;
   int32_t m_iCaptureBtn;
   int32_t m_iSysBox;
   bool m_bLButtonDown;
   bool m_bMaximized;
   bool m_bSetMaximize;
   bool m_bDoModalFlag;
 };
 
 #endif  // XFA_FWL_CFWL_FORM_H_