Remove addToStore variant as requested by `FIXME`

The idea is it's always more flexible to consumer a `Source` than a
plain string, and it might even reduce memory consumption.

I also looked at `addToStoreFromDump` with its `// FIXME: remove?`, but
the worked needed for that is far more up for interpretation, so I
punted for now.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/libfetchers/tarball.cc b/src/libfetchers/tarball.cc
index bf2b2a5ff..b6e57379b 100644
--- a/src/libfetchers/tarball.cc
+++ b/src/libfetchers/tarball.cc
@@ -71,7 +71,8 @@ DownloadFileResult downloadFile(
         info.narHash = hashString(htSHA256, *sink.s);
         info.narSize = sink.s->size();
         info.ca = makeFixedOutputCA(FileIngestionMethod::Flat, hash);
-        store->addToStore(info, sink.s, NoRepair, NoCheckSigs);
+        auto source = StringSource { *sink.s };
+        store->addToStore(info, source, NoRepair, NoCheckSigs);
         storePath = std::move(info.path);
     }