Remove some trailing whitespace.

src/librustc_incremental/persist/save.rs

@@ -189,7 +189,7 @@ struct Stat {
 
         let total_node_count = serialized_graph.nodes.len();
         let total_edge_count = serialized_graph.edge_list_data.len();
-        let (total_edge_reads, total_duplicate_edge_reads) = 
+        let (total_edge_reads, total_duplicate_edge_reads) =
             tcx.dep_graph.edge_deduplication_data();
 
         let mut counts: FxHashMap<_, Stat> = FxHashMap();