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

lib/codegen/src/legalizer/boundary.rs

@@ -575,7 +575,8 @@ pub fn handle_return_abi(inst: Inst, func: &mut Function, cfg: &ControlFlowGraph
             rt.purpose == ArgumentPurpose::Link
                 || rt.purpose == ArgumentPurpose::StructReturn
                 || rt.purpose == ArgumentPurpose::VMContext
-        }).count();
+        })
+        .count();
     let abi_args = func.signature.returns.len() - special_args;
 
     let pos = &mut FuncCursor::new(func).at_inst(inst);
@@ -694,7 +695,8 @@ fn spill_call_arguments(pos: &mut FuncCursor) -> bool {
                     }
                     _ => None,
                 }
-            }).collect::<Vec<_>>()
+            })
+            .collect::<Vec<_>>()
     };
 
     if arglist.is_empty() {

lib/codegen/src/legalizer/split.rs

@@ -165,7 +165,8 @@ fn split_any(
                     .get_mut(
                         num_fixed_args + repair.hi_num,
                         &mut pos.func.dfg.value_lists,
-                    ).unwrap() = hi;
+                    )
+                    .unwrap() = hi;
             } else {
                 // We need to append one or more arguments. If we're adding more than one argument,
                 // there must be pending repairs on the stack that will fill in the correct values