Migrate test block 10 to Dart 2.0.

tests/corelib_2/iterable_element_at_test.dart

 // Copyright (c) 2012, 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:expect/expect.dart";
 
 main() {
   List<int> list1 = <int>[1, 2, 3];
   List<int> list2 = const <int>[4, 5, 6];
   List<String> list3 = <String>[];
   Set<int> set1 = new Set<int>();
   set1..add(11)..add(12)..add(13);
   Set set2 = new Set();
 
   Expect.equals(1, list1.elementAt(0));
   Expect.equals(2, list1.elementAt(1));
   Expect.equals(3, list1.elementAt(2));
-  Expect.throws(
-      () => list1.elementAt("2"), (e) => e is ArgumentError || e is TypeError);
+  list1.elementAt("2"); //# static: compile-time error
   Expect.throws(() => list1.elementAt(-1), (e) => e is ArgumentError);
   Expect.throws(() => list1.elementAt(3), (e) => e is RangeError);
 
   Expect.equals(4, list2.elementAt(0));
   Expect.equals(5, list2.elementAt(1));
   Expect.equals(6, list2.elementAt(2));
-  Expect.throws(
-      () => list2.elementAt("2"), (e) => e is ArgumentError || e is TypeError);
+  list2.elementAt("2"); //# static: compile-time error
   Expect.throws(() => list2.elementAt(-1), (e) => e is ArgumentError);
   Expect.throws(() => list2.elementAt(3), (e) => e is RangeError);
 
   Expect.isTrue(set1.contains(set1.elementAt(0)));
   Expect.isTrue(set1.contains(set1.elementAt(1)));
   Expect.isTrue(set1.contains(set1.elementAt(2)));
   Expect.throws(() => set1.elementAt(-1), (e) => e is ArgumentError);
   Expect.throws(() => set1.elementAt(3), (e) => e is RangeError);
 
-  Expect.throws(
-      () => set2.elementAt("2"), (e) => e is ArgumentError || e is TypeError);
+  set2.elementAt("2"); //# static: compile-time error
   Expect.throws(() => set2.elementAt(-1), (e) => e is ArgumentError);
   Expect.throws(() => set2.elementAt(0), (e) => e is RangeError);
   Expect.throws(() => set2.elementAt(1), (e) => e is RangeError);
 }