RefCount CPDF_StreamAcc all the time.

Pass stream argument to constructor; it feels like a
stream accessor should always be made from a stream rather
than passing one in after the fact.

Change-Id: Iaa46cb37677b81f0170f5d39bab76ad38ea4af44
Reviewed-on: https://pdfium-review.googlesource.com/3620
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
diff --git a/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp b/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
index 4c8591e..bd16f43 100644
--- a/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
+++ b/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
@@ -497,8 +497,8 @@
         fileWrite->WriteBlock(content.c_str(), fileWrite->GetSize(),
                               content.GetLength());
       }
-      auto pAcc = pdfium::MakeUnique<CPDF_StreamAcc>();
-      pAcc->LoadAllData(pStream);
+      auto pAcc = pdfium::MakeRetain<CPDF_StreamAcc>(pStream);
+      pAcc->LoadAllData();
       fileWrite->WriteBlock(pAcc->GetData(), fileWrite->GetSize(),
                             pAcc->GetSize());
     }