Add some tests for calls with checks in strong mode.

tests/language_strong/covariant_subtyping_tearoff1_test.dart

Index: tests/language_strong/covariant_subtyping_tearoff1_test.dart
diff --git a/tests/language_strong/covariant_subtyping_unsafe_call1_test.dart b/tests/language_strong/covariant_subtyping_tearoff1_test.dart
similarity index 65%
copy from tests/language_strong/covariant_subtyping_unsafe_call1_test.dart
copy to tests/language_strong/covariant_subtyping_tearoff1_test.dart
index 79fced239fae75c0396c9b98a9c4bf2c5d9d7b56..404b4bbdeb54494094630cd94df51404be1ca667 100644
--- a/tests/language_strong/covariant_subtyping_unsafe_call1_test.dart
+++ b/tests/language_strong/covariant_subtyping_tearoff1_test.dart
@@ -4,11 +4,16 @@
 import 'package:expect/expect.dart';
 
 class Foo<T> {
-  method(T x) {}
+  dynamic method(T x) {}
 }
 
+typedef dynamic TakeNum(num x);
+
 main() {
   Foo<int> intFoo = new Foo<int>();
   Foo<num> numFoo = intFoo;
-  Expect.throws(() => numFoo.method(2.5));
+  TakeNum f = numFoo.method;
+  Expect.throws(() => f(2.5));
+  dynamic f2 = numFoo.method;
+  Expect.throws(() => f2(2.5));
 }