fix #26393, treat tear offs as definite functions

pkg/analyzer/test/src/task/strong/checker_test.dart

 // Copyright (c) 2015, 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.
 
 library analyzer.test.src.task.strong.checker_test;
 
 import '../../../reflective_tests.dart';
 import 'strong_test_helper.dart';
 
 void main() {
@@ skipping 2658 matching lines @@
 }
 
 class B implements A {}
 
 class F {
   void f(x) {}
   void g(int x) {}
 }
 
 class G extends F {
   /*error:INVALID_METHOD_OVERRIDE*/void f(int x) {}

[vsm, 2016/08/08 20:07:14]

Ah - looks like we're already testing that F.f has a strict type wrt override
checking.  :-)

[Jennifer Messerly, 2016/08/08 21:21:13]

oh! yes I should've mentioned that, I also did a manual test and confirmed it
was handled correctly for overrides.

   void g(dynamic x) {}
 }
 
 class H implements F {
   /*error:INVALID_METHOD_OVERRIDE*/void f(int x) {}
   void g(dynamic x) {}
 }
 ''');
   }
 
+  void test_methodTearoffStrictArrow() {
+    // Regression test for https://github.com/dart-lang/sdk/issues/26393
+    checkFile(r'''
+class A {
+  void foo(dynamic x) {}
+  void test(void f(int x)) {
+    test(foo);
+  }
+}
+    ''');
+  }
+
   void test_mixinOverrideOfGrandInterface_interfaceOfAbstractSuperclass() {
     checkFile('''
 class A {}
 class B {}
 
 abstract class I1 {
     m(A a);
 }
 abstract class Base implements I1 {}
 
@@ skipping 948 matching lines @@
     // Regression test for https://github.com/dart-lang/sdk/issues/25069
     checkFile('''
 typedef int Foo();
 void foo() {}
 void main () {
   Foo x = /*error:INVALID_ASSIGNMENT,info:USE_OF_VOID_RESULT*/foo();
 }
 ''');
   }
 }