Cleanup remaining IFWL files for visiblity and usage.

xfa/fwl/core/cfwl_picturebox.cpp

Index: xfa/fwl/core/cfwl_picturebox.cpp
diff --git a/xfa/fwl/core/cfwl_picturebox.cpp b/xfa/fwl/core/cfwl_picturebox.cpp
index 8badc999ea5e1723fbbfec05da7c4774fc7489d2..b701ae7ebaa76950cfaf6640f6ced5e3a0daaf4b 100644
--- a/xfa/fwl/core/cfwl_picturebox.cpp
+++ b/xfa/fwl/core/cfwl_picturebox.cpp
@@ -114,7 +114,7 @@ int32_t CFWL_PictureBox::GetOpacity(IFWL_Widget* pWidget) {
   return m_iOpacity;
 }
 
-FWL_Error CFWL_PictureBox::GetMatrix(IFWL_Widget* pWidget, CFX_Matrix& matrix) {
+void CFWL_PictureBox::GetMatrix(IFWL_Widget* pWidget, CFX_Matrix& matrix) {
   CFX_RectF rect;
   pWidget->GetClientRect(rect);
   FX_FLOAT fLen = rect.width / 2;
@@ -125,7 +125,6 @@ FWL_Error CFWL_PictureBox::GetMatrix(IFWL_Widget* pWidget, CFX_Matrix& matrix) {
   matrix.Translate(fLen, fWid);
   matrix.Scale(m_fScaleX, m_fScaleY);
   matrix.Translate(m_fOffSetX, m_fOffSetY);
-  return FWL_Error::Succeeded;
 }
 
 int32_t CFWL_PictureBox::GetFlipMode(IFWL_Widget* pWidget) {