[ESNext] Implement DynamicImportCall

test/mjsunit/harmony/modules-import-13.js

+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax --harmony-dynamic-import
+
+ran = false;
+async function test1() {
+  try {
+    let x = { toString() { return 'modules-skip-1.js' } };
+    let namespace = await import(x);
+    let life = namespace.life();
+    assertEquals(42, life);
+    ran = true;
+  } catch(e) {
+    %AbortJS('failure: '+ e);
+  }
+}
+
+test1();
+%RunMicrotasks();
+assertTrue(ran);
+
+ran = false;
+async function test2() {
+  try {
+    let x = { get toString() { return () => 'modules-skip-1.js' } };
+    let namespace = await import(x);
+    let life = namespace.life();
+    assertEquals(42, life);
+    ran = true;
+  } catch(e) {
+    %AbortJS('failure: '+ e);
+  }
+}
+
+test2();
+%RunMicrotasks();
+assertTrue(ran);