fix nll reference harder

Author: nikomatsakis

src/test/ui/nll/get_default.nll.stderr

@@ -41,7 +41,7 @@ LL |         match map.get() {
    |               --- immutable borrow occurs here
 ...
 LL |                 map.set(String::new()); // Ideally, this would not error.
-   |                 ^^^ mutable borrow occurs here
+   |                 ^^^^^^^^^^^^^^^^^^^^^^ mutable borrow occurs here
    |
 note: borrowed value must be valid for the anonymous lifetime #1 defined on the function body at 26:1...
   --> $DIR/get_default.rs:26:1
@@ -55,14 +55,26 @@ LL | |     }
 LL | | }
    | |_^
 
+error[E0502]: cannot borrow `*map` as mutable because it is also borrowed as immutable (Mir)
+  --> $DIR/get_default.rs:45:17
+   |
+LL |         match map.get() {
+   |               --- immutable borrow occurs here
+LL |             Some(v) => {
+LL |                 map.set(String::new()); // Both AST and MIR error here
+   |                 ^^^^^^^^^^^^^^^^^^^^^^ mutable borrow occurs here
+...
+LL |                 return v;
+   |                        - borrow later used here
+
 error[E0502]: cannot borrow `*map` as mutable because it is also borrowed as immutable (Mir)
   --> $DIR/get_default.rs:51:17
    |
 LL |         match map.get() {
    |               --- immutable borrow occurs here
 ...
 LL |                 map.set(String::new()); // Ideally, just AST would error here
-   |                 ^^^ mutable borrow occurs here
+   |                 ^^^^^^^^^^^^^^^^^^^^^^ mutable borrow occurs here
    |
 note: borrowed value must be valid for the anonymous lifetime #1 defined on the function body at 41:1...
   --> $DIR/get_default.rs:41:1
@@ -76,18 +88,6 @@ LL | |     }
 LL | | }
    | |_^
 
-error[E0502]: cannot borrow `*map` as mutable because it is also borrowed as immutable (Mir)
-  --> $DIR/get_default.rs:45:17
-   |
-LL |         match map.get() {
-   |               --- immutable borrow occurs here
-LL |             Some(v) => {
-LL |                 map.set(String::new()); // Both AST and MIR error here
-   |                 ^^^ mutable borrow occurs here
-...
-LL |                 return v;
-   |                        - borrow later used here
-
 error: aborting due to 6 previous errors
 
 For more information about this error, try `rustc --explain E0502`.