Extract x_Driver tests that time out on Windows bots.

pkg/analyzer/test/generated/static_warning_code_driver_test.dart

+// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'static_warning_code_test.dart';
+
+main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(StaticWarningCodeTest_Driver);
+  });
+}
+
+@reflectiveTest
+class StaticWarningCodeTest_Driver extends StaticWarningCodeTest {
+  @override
+  bool get enableNewAnalysisDriver => true;
+
+  @failingTest
+  @override
+  test_argumentTypeNotAssignable_ambiguousClassName() {
+    return super.test_argumentTypeNotAssignable_ambiguousClassName();
+  }
+
+  @failingTest
+  @override
+  test_importOfNonLibrary() {
+    return super.test_importOfNonLibrary();
+  }
+}