For scikit-hep/uproot5#407 (#63)

* Add uproot-issue407.root

* uproot-issue407.root -> uproot-issue-407.root, fix macro name

* restore uproot-issue407.root

dev/make-root/uproot_issue_407.C

@@ -0,0 +1,41 @@
+#include <TDatime.h>
+#include <TFile.h>
+#include <TObject.h>
+#include <TTree.h>
+
+class TFoo : public TObject {
+public:
+  TDatime d;
+ClassDef(TFoo, 1);
+};
+
+class TFooPadded : public TObject {
+public:
+  TDatime d;
+  // Pad the object to increase its size to fit version header that
+  // TDatetime doesn't stream.  This is not needed for a test, but
+  // shows a different error when custom streamer is not implemented.
+  char pad[6];
+ClassDef(TFooPadded, 1);
+};
+
+// Streaming interpreted classes is not supported, so this has to be ran with ACLiC:
+//
+//   root -lbq uproot_issue_407.C+
+//
+void uproot_issue_407() {
+  TFile f("uproot-issue-407.root", "RECREATE");
+  TTree tree;
+  TDatime d;
+  tree.Branch("branch", &d);
+  d.Set(2021, 1, 1, 0, 0, 0);
+  tree.Fill();
+  tree.Fill();
+  tree.Write("tree");
+  TFoo foo;
+  foo.d.Set(2021, 1, 1, 0, 0, 0);
+  foo.Write("foo");
+  TFooPadded foo_padded;
+  foo_padded.d.Set(2021, 1, 1, 0, 0, 0);
+  foo_padded.Write("foo_padded");
+}