Update to the rustfmt in rust 1.31, which is now stable.

lib/codegen/src/verifier/mod.rs

@@ -887,11 +887,11 @@ impl<'a> Verifier<'a> {
                     );
                 }
                 // The defining EBB dominates the instruction using this value.
-                if is_reachable && !self.expected_domtree.dominates(
-                    ebb,
-                    loc_inst,
-                    &self.func.layout,
-                ) {
+                if is_reachable
+                    && !self
+                        .expected_domtree
+                        .dominates(ebb, loc_inst, &self.func.layout)
+                {
                     return fatal!(
                         errors,
                         loc_inst,
@@ -1559,7 +1559,8 @@ impl<'a> Verifier<'a> {
                     &self.func,
                     &self.func.dfg[inst],
                     self.func.dfg.ctrl_typevar(inst),
-                ).peekable();
+                )
+                .peekable();
 
             if encodings.peek().is_none() {
                 return nonfatal!(