Refcount all the IFX_ stream classes all the time.

fpdfsdk/cpdfsdk_formfillenvironment.cpp

Index: fpdfsdk/cpdfsdk_formfillenvironment.cpp
diff --git a/fpdfsdk/cpdfsdk_formfillenvironment.cpp b/fpdfsdk/cpdfsdk_formfillenvironment.cpp
index ee7758c281c8d939156a296736cd14c9ebefe8fd..b91c97842f7ddf324c6957f7016b0b5a2b49e9d9 100644
--- a/fpdfsdk/cpdfsdk_formfillenvironment.cpp
+++ b/fpdfsdk/cpdfsdk_formfillenvironment.cpp
@@ -462,8 +462,8 @@ FPDF_FILEHANDLER* CPDFSDK_FormFillEnvironment::OpenFile(int fileType,
   return nullptr;
 }
 
-IFX_SeekableReadStream* CPDFSDK_FormFillEnvironment::DownloadFromURL(
-    const FX_WCHAR* url) {
+CFX_RetainPtr<IFX_SeekableReadStream>
+CPDFSDK_FormFillEnvironment::DownloadFromURL(const FX_WCHAR* url) {
   if (!m_pInfo || !m_pInfo->FFI_DownloadFromURL)
     return nullptr;
 
@@ -472,7 +472,6 @@ IFX_SeekableReadStream* CPDFSDK_FormFillEnvironment::DownloadFromURL(
       (FPDF_WIDESTRING)bstrURL.GetBuffer(bstrURL.GetLength());
 
   FPDF_LPFILEHANDLER fileHandler = m_pInfo->FFI_DownloadFromURL(m_pInfo, wsURL);
-
   return MakeSeekableStream(fileHandler);
 }