Refcount all the IFX_ stream classes all the time.

fpdfsdk/fpdfxfa/cpdfxfa_context.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 FPDFSDK_FPDFXFA_CPDFXFA_CONTEXT_H_
 #define FPDFSDK_FPDFXFA_CPDFXFA_CONTEXT_H_
 
 #include <memory>
@@ skipping 49 matching lines @@
 
   void Beep(uint32_t dwType) override;
   int32_t MsgBox(const CFX_WideString& wsMessage,
                  const CFX_WideString& wsTitle,
                  uint32_t dwIconType,
                  uint32_t dwButtonType) override;
   CFX_WideString Response(const CFX_WideString& wsQuestion,
                           const CFX_WideString& wsTitle,
                           const CFX_WideString& wsDefaultAnswer,
                           bool bMark) override;
-  IFX_SeekableReadStream* DownloadURL(const CFX_WideString& wsURL) override;
+  CFX_RetainPtr<IFX_SeekableReadStream> DownloadURL(
+      const CFX_WideString& wsURL) override;
   bool PostRequestURL(const CFX_WideString& wsURL,
                       const CFX_WideString& wsData,
                       const CFX_WideString& wsContentType,
                       const CFX_WideString& wsEncode,
                       const CFX_WideString& wsHeader,
                       CFX_WideString& wsResponse) override;
   bool PutRequestURL(const CFX_WideString& wsURL,
                      const CFX_WideString& wsData,
                      const CFX_WideString& wsEncode) override;
 
@@ skipping 26 matching lines @@
   std::unique_ptr<CJS_Runtime> m_pRuntime;
   CFX_ArrayTemplate<CPDFXFA_Page*> m_XFAPageList;
   LoadStatus m_nLoadStatus;
   int m_nPageCount;
 
   // Must be destroyed before |m_pFormFillEnv|.
   CPDFXFA_DocEnvironment m_DocEnv;
 };
 
 #endif  // FPDFSDK_FPDFXFA_CPDFXFA_CONTEXT_H_