Allow await property names in async functions

Co-authored-by: hvitved <3667920+hvitved@users.noreply.github.com>

Author: Copilot

javascript/extractor/src/com/semmle/jcorn/Parser.java

@@ -2296,9 +2296,9 @@ protected Identifier parseIdent(boolean liberal) {
           && (this.options.ecmaVersion() >= 6
               || inputSubstring(this.start, this.end).indexOf("\\") == -1))
         this.raiseRecoverable(this.start, "The keyword '" + this.value + "' is reserved");
-      if (!isPrivateField && this.inGenerator && this.value.equals("yield"))
+      if (!liberal && !isPrivateField && this.inGenerator && this.value.equals("yield"))
         this.raiseRecoverable(this.start, "Can not use 'yield' as identifier inside a generator");
-      if (!isPrivateField && this.inAsync && this.value.equals("await"))
+      if (!liberal && !isPrivateField && this.inAsync && this.value.equals("await"))
         this.raiseRecoverable(
             this.start, "Can not use 'await' as identifier inside an async function");
       name = String.valueOf(this.value);

javascript/ql/test/library-tests/AwaitPropertyName/AwaitPropertyName.expected

@@ -0,0 +1,5 @@
+import javascript
+
+from Expr e
+where e.toString() = "this expression should not exist"
+select e

javascript/ql/test/library-tests/AwaitPropertyName/AwaitPropertyName.ql

@@ -0,0 +1,5 @@
+const pool = { await() { return 42; } };
+
+async function issue22499() {
+  return await pool.await();
+}