mach: Do not use unstable rust for `rustfmt` (#31441)

We can use stable rust if we pass the unstable configuration as
command-line arguments to rustfmt itself. This prevents needing to
install an unstable rust toolchain.

The one downside here is that it doesn't seem that "ignore" is
supported so we have to start formatting the files in "third_party."
This shouldn't be a huge issue because we don't plan to check much more
rust code into those directories.

1 files changed, 8 insertions, 5 deletions

diff --git a/components/script/dom/bindings/buffer_source.rs b/components/script/dom/bindings/buffer_source.rs
index 031ecf9c185..80fa00e408b 100644
--- a/components/script/dom/bindings/buffer_source.rs
+++ b/components/script/dom/bindings/buffer_source.rs
@@ -269,8 +269,10 @@ where
                 buffer.get()
             },
         });
-        let Ok(array) = array as Result<CustomAutoRooterGuard<'_, TypedArray<T, *mut JSObject>>, &mut ()> else{
-             return Err(())
+        let Ok(array) =
+            array as Result<CustomAutoRooterGuard<'_, TypedArray<T, *mut JSObject>>, &mut ()>
+        else {
+            return Err(());
         };
         unsafe {
             let slice = (*array).as_slice();
@@ -305,9 +307,10 @@ where
                 buffer.get()
             },
         });
-        let Ok(mut array) =  array as Result<CustomAutoRooterGuard<'_, TypedArray<T, *mut JSObject>>, &mut ()> else
-        {
-            return Err(())
+        let Ok(mut array) =
+            array as Result<CustomAutoRooterGuard<'_, TypedArray<T, *mut JSObject>>, &mut ()>
+        else {
+            return Err(());
         };
         unsafe {
             let slice = (*array).as_mut_slice();