Use pre-interned symbols in import recovery

Author: bjorn3

compiler/rustc_parse/src/parser/item.rs

@@ -271,8 +271,7 @@ impl<'a> Parser<'a> {
             // MACRO_RULES ITEM
             self.parse_item_macro_rules(vis, has_bang)?
         } else if self.isnt_macro_invocation()
-            && (self.token.is_ident_named(Symbol::intern("import"))
-                || self.token.is_ident_named(Symbol::intern("using")))
+            && (self.token.is_ident_named(sym::import) || self.token.is_ident_named(sym::using))
         {
             return self.recover_import_as_use();
         } else if self.isnt_macro_invocation() && vis.kind.is_pub() {

compiler/rustc_span/src/symbol.rs

@@ -782,6 +782,7 @@ symbols! {
         impl_lint_pass,
         impl_macros,
         impl_trait_in_bindings,
+        import,
         import_shadowing,
         imported_main,
         in_band_lifetimes,
@@ -1519,6 +1520,7 @@ symbols! {
         use_nested_groups,
         used,
         used_with_arg,
+        using,
         usize,
         v1,
         va_arg,