Add a query for CapturedPlace::to_symbol

compiler/rustc_middle/src/query/mod.rs

@@ -329,6 +329,16 @@ rustc_queries! {
         }
     }
 
+    query symbols_for_closure_captures(
+        key: (LocalDefId, DefId)
+    ) -> Vec<rustc_span::Symbol> {
+        desc {
+            |tcx| "symbols for captures of closure `{}` in `{}`",
+            tcx.def_path_str(key.1),
+            tcx.def_path_str(key.0.to_def_id())
+        }
+    }
+
     /// MIR after our optimization passes have run. This is MIR that is ready
     /// for codegen. This is also the only query that can fetch non-local MIR, at present.
     query optimized_mir(key: DefId) -> &'tcx mir::Body<'tcx> {