Change _PDF_RenderItem to CPDF_RenderContext::Layer.

fpdfsdk/src/fpdfview.cpp

Index: fpdfsdk/src/fpdfview.cpp
diff --git a/fpdfsdk/src/fpdfview.cpp b/fpdfsdk/src/fpdfview.cpp
index d713e9773d85994a18f4b46298dffa8a77a28229..3bffa91a8b8bf9c7a6bf7b054dacc82a93f8adcb 100644
--- a/fpdfsdk/src/fpdfview.cpp
+++ b/fpdfsdk/src/fpdfview.cpp
@@ -739,7 +739,7 @@ void FPDF_RenderPage_Retail(CRenderContext* pContext,
   pContext->m_pDevice->SetClip_Rect(&clip);
 
   pContext->m_pContext = new CPDF_RenderContext(pPage);
-  pContext->m_pContext->AppendObjectList(pPage, &matrix);
+  pContext->m_pContext->AppendLayer(pPage, &matrix);
 
   if (flags & FPDF_ANNOT) {
     pContext->m_pAnnots = new CPDF_AnnotList(pPage);