[fix issue in return unboxing optimization that would sometimes re-create constants on the heap
John Meacham <john@repetae.net>**20090828010825
 Ignore-this: ca2a43e120adcef3c783cf2ac7df3295
] hunk ./src/Grin/SSimplify.hs 335
-    g x@UnUnknown {} _ = x
-    g _ x@UnUnknown {} = x
+    g x _ = UnUnknown (getType x)
hunk ./src/Grin/SSimplify.hs 346
-    g (NodeC t xs) = UnNode t (map g xs) tyDNode
hunk ./src/Grin/SSimplify.hs 347
+    g (NodeC t xs) = UnNode t (map g xs) tyDNode