Rollup merge of #112677 - the8472:remove-unusued-field, r=JohnTitor

remove unused field

Followup to #104455. The field is no longer needed since ExtractIf (previously DrainFilter) doesn't keep draining in its drop impl.

library/alloc/src/vec/mod.rs

@@ -2948,7 +2948,7 @@ impl<T, A: Allocator> Vec<T, A> {
             self.set_len(0);
         }
 
-        ExtractIf { vec: self, idx: 0, del: 0, old_len, pred: filter, panic_flag: false }
+        ExtractIf { vec: self, idx: 0, del: 0, old_len, pred: filter }
     }
 }