Revert "Delete empty downloaded file when wget fails, to work around reported resume failure."

This reverts commit 98886e3fbf.

Better fix forthcoming

Utility/Url.hs

@@ -118,16 +118,8 @@ download' quiet url headers options file =
 	 - downloaded before the resume. -}
 	curl = go "curl" $ headerparams ++ quietopt "-s" ++
 		[Params "-f -L -C - -# -o"]
-	go cmd opts = do
-		ok <- boolSystem cmd $
-			options++opts++[File file, File url]
-		-- wget sometimes leaves behind an empty file on failure;
-		-- remove this as it sometimes interferes with a re-download
-		unless ok $ do
-			size <- catchMaybeIO $ fileSize <$> getFileStatus file
-			when (size == Just 0) $
-				removeFile file
-		return ok
+	go cmd opts = boolSystem cmd $
+		options++opts++[File file, File url]
 	quietopt s
 		| quiet = [Param s]
 		| otherwise = []