Fix formatting issue

Keep `downcast_unchecked` method on the same line as the closing
parenthesis of the chopped-down call to `Widget::from_glib_none`.

Author: demurgos

src/file_chooser_dialog.rs

@@ -24,8 +24,7 @@ impl FileChooserDialog {
                 parent.to_glib_none().0,
                 action.to_glib(),
                 ptr::null::<c_char>()
-            ))
-                .downcast_unchecked()
+            )).downcast_unchecked()
         }
     }
 
@@ -82,8 +81,7 @@ impl FileChooserDialog {
                     //       See: https://github.com/rust-lang/rust/issues/44930
                     panic!(format!("`FileChooserDialog::with_buttons` does not support 4+ buttons, received {}", buttons.len()))
                 }
-            })
-              .downcast_unchecked()
+            }).downcast_unchecked()
         }
     }
 }