Fix asyncDelegator reporting "done" too early (#51274)

* Fix asyncDelegator reporting done too early

* Add unit test for yields inside finally block

See #45400

src/testRunner/unittests/evaluation/asyncGenerator.ts

@@ -30,4 +30,30 @@ describe("unittests:: evaluation:: asyncGeneratorEvaluation", () => {
             { value: 0, done: true }
         ]);
     });
+    it("yields in finally block with async delegator (es2017)", async () => {
+        const result = evaluator.evaluateTypeScript(`
+        async function* g1() {
+            try {
+                yield 1;
+            } finally {
+                yield 2;
+            }
+        }
+        async function* g2() {
+            yield* g1();
+        }
+        export const output: any[] = [];
+        export async function main() {
+            const it = g2();
+            output.push(await it.next());
+            output.push(await it.return());
+            output.push(await it.next());
+        }`, { target: ts.ScriptTarget.ES2017 });
+        await result.main();
+        assert.deepEqual(result.output, [
+            { done: false, value: 1 },
+            { done: false, value: 2 },
+            { done: true, value: undefined }
+        ]);
+    });
 });