Update tests wrt. bind_by_by_move_pattern_guards stabilization.

Author: Centril

src/librustc_mir/error_codes.rs

@@ -1989,7 +1989,6 @@ When matching on a variable it cannot be mutated in the match guards, as this
 could cause the match to be non-exhaustive:
 
 ```compile_fail,E0510
-#![feature(bind_by_move_pattern_guards)]
 let mut x = Some(0);
 match x {
     None => (),

src/test/mir-opt/match-arm-scopes.rs

@@ -8,8 +8,6 @@
 //   all of the bindings for that scope.
 // * No drop flags are used.
 
-#![feature(nll, bind_by_move_pattern_guards)]
-
 fn complicated_match(cond: bool, items: (bool, bool, String)) -> i32 {
     match items {
         (false, a, s) | (a, false, s) if if cond { return 3 } else { a } => 1,

src/test/ui/bind-by-move/bind-by-move-no-guards.rs

@@ -8,12 +8,9 @@ fn foo() -> isize {
     let mut x = Enum::A(&mut n);
     match x {
         Enum::A(_) if { x = Enum::B(false); false } => 1,
-        //~^ ERROR cannot assign in a pattern guard
-        //~| ERROR cannot assign `x` in match guard
+        //~^ ERROR cannot assign `x` in match guard
         Enum::A(_) if { let y = &mut x; *y = Enum::B(false); false } => 1,
-        //~^ ERROR cannot mutably borrow in a pattern guard
-        //~| ERROR cannot assign in a pattern guard
-        //~| ERROR cannot mutably borrow `x` in match guard
+        //~^ ERROR cannot mutably borrow `x` in match guard
         Enum::A(p) => *p,
         Enum::B(_) => 2,
     }

src/test/ui/bind-by-move/bind-by-move-no-guards.stderr

@@ -1,23 +1,3 @@
-error[E0302]: cannot assign in a pattern guard
-  --> $DIR/borrowck-mutate-in-guard.rs:10:25
-   |
-LL |         Enum::A(_) if { x = Enum::B(false); false } => 1,
-   |                         ^^^^^^^^^^^^^^^^^^ assignment in pattern guard
-
-error[E0301]: cannot mutably borrow in a pattern guard
-  --> $DIR/borrowck-mutate-in-guard.rs:13:38
-   |
-LL |         Enum::A(_) if { let y = &mut x; *y = Enum::B(false); false } => 1,
-   |                                      ^ borrowed mutably in pattern guard
-   |
-   = help: add `#![feature(bind_by_move_pattern_guards)]` to the crate attributes to enable
-
-error[E0302]: cannot assign in a pattern guard
-  --> $DIR/borrowck-mutate-in-guard.rs:13:41
-   |
-LL |         Enum::A(_) if { let y = &mut x; *y = Enum::B(false); false } => 1,
-   |                                         ^^^^^^^^^^^^^^^^^^^ assignment in pattern guard
-
 error[E0510]: cannot assign `x` in match guard
   --> $DIR/borrowck-mutate-in-guard.rs:10:25
    |
@@ -27,15 +7,14 @@ LL |         Enum::A(_) if { x = Enum::B(false); false } => 1,
    |                         ^^^^^^^^^^^^^^^^^^ cannot assign
 
 error[E0510]: cannot mutably borrow `x` in match guard
-  --> $DIR/borrowck-mutate-in-guard.rs:13:33
+  --> $DIR/borrowck-mutate-in-guard.rs:12:33
    |
 LL |     match x {
    |           - value is immutable in match guard
 ...
 LL |         Enum::A(_) if { let y = &mut x; *y = Enum::B(false); false } => 1,
    |                                 ^^^^^^ cannot mutably borrow
 
-error: aborting due to 5 previous errors
+error: aborting due to 2 previous errors
 
-Some errors have detailed explanations: E0301, E0302, E0510.
-For more information about an error, try `rustc --explain E0301`.
+For more information about this error, try `rustc --explain E0510`.

src/test/ui/borrowck/borrowck-mutate-in-guard.rs

@@ -1,7 +1,7 @@
 fn main() {
     match Some(()) {
         None => { },
-        option if option.take().is_none() => {}, //~ ERROR E0301
+        option if option.take().is_none() => {},
         Some(_) => { } //~^ ERROR E0596
     }
 }

src/test/ui/borrowck/borrowck-mutate-in-guard.stderr

@@ -1,11 +1,3 @@
-error[E0301]: cannot mutably borrow in a pattern guard
-  --> $DIR/E0301.rs:4:19
-   |
-LL |         option if option.take().is_none() => {},
-   |                   ^^^^^^ borrowed mutably in pattern guard
-   |
-   = help: add `#![feature(bind_by_move_pattern_guards)]` to the crate attributes to enable
-
 error[E0596]: cannot borrow `option` as mutable, as it is immutable for the pattern guard
   --> $DIR/E0301.rs:4:19
    |
@@ -14,7 +6,6 @@ LL |         option if option.take().is_none() => {},
    |
    = note: variables bound in patterns are immutable until the end of the pattern guard
 
-error: aborting due to 2 previous errors
+error: aborting due to previous error
 
-Some errors have detailed explanations: E0301, E0596.
-For more information about an error, try `rustc --explain E0301`.
+For more information about this error, try `rustc --explain E0596`.