Make CPDF_Path have a CFX_Path rather than inheriting

fpdfsdk/fxedit/fxet_edit.cpp

Index: fpdfsdk/fxedit/fxet_edit.cpp
diff --git a/fpdfsdk/fxedit/fxet_edit.cpp b/fpdfsdk/fxedit/fxet_edit.cpp
index 098ef7f10bf362a06325a1cb4a8b4467d438540d..7d207a83caaee26fc8eb5ac3cf3001cd8f659efe 100644
--- a/fpdfsdk/fxedit/fxet_edit.cpp
+++ b/fpdfsdk/fxedit/fxet_edit.cpp
@@ -137,8 +137,8 @@ void AddRectToPageObjects(CPDF_PageObjectHolder* pObjectHolder,
                           FX_COLORREF crFill,
                           const CFX_FloatRect& rcFill) {
   std::unique_ptr<CPDF_PathObject> pPathObj(new CPDF_PathObject);
-  CFX_PathData* pPathData = pPathObj->m_Path.GetPrivateCopy();
-  pPathData->AppendRect(rcFill.left, rcFill.bottom, rcFill.right, rcFill.top);
+  pPathObj->m_Path.AppendRect(rcFill.left, rcFill.bottom, rcFill.right,
+                              rcFill.top);
 
   FX_FLOAT rgb[3];
   rgb[0] = FXARGB_R(crFill) / 255.0f;