Refcount all the IFX_ stream classes all the time.

fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.h

Index: fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.h
diff --git a/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.h b/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.h
index a7d41a88c8a1bbb85c8b759ea5e15b6d601a6eff..d7cb1696168cda5ab743e9a17a1a1a7cc6c2b156 100644
--- a/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.h
+++ b/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.h
@@ -7,6 +7,7 @@
 #ifndef FPDFSDK_FPDFXFA_CPDFXFA_DOCENVIRONMENT_H_
 #define FPDFSDK_FPDFXFA_CPDFXFA_DOCENVIRONMENT_H_
 
+#include "core/fxcrt/cfx_retain_ptr.h"
 #include "public/fpdfview.h"
 #include "xfa/fxfa/fxfa.h"
 
@@ -85,8 +86,9 @@ class CPDFXFA_DocEnvironment : public IXFA_DocEnvironment {
                          const CFX_ByteStringC& szPropName,
                          CFXJSE_Value* pValue) override;
 
-  IFX_SeekableReadStream* OpenLinkedFile(CXFA_FFDoc* hDoc,
-                                         const CFX_WideString& wsLink) override;
+  CFX_RetainPtr<IFX_SeekableReadStream> OpenLinkedFile(
+      CXFA_FFDoc* hDoc,
+      const CFX_WideString& wsLink) override;
 
  private:
   bool OnBeforeNotifySubmit();