Verify that inference ignores setters with function-typed arguments.

pkg/front_end/testcases/inference/infer_setter_function_typed.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.
+
+/*@testedFeatures=inference*/
+library test;
+
+// The `value` parameter for `B::x=` has a type, so it should not be inferred
+// based on `A::x=`.
+
+typedef int F();
+
+abstract class A {
+  void set x(F value);
+}
+
+abstract class B extends A {
+  void set x(value());
+}
+
+T f<T>() => null;
+
+g(B b) {
+  b. /*@target=B::x*/ x = /*@typeArgs=() -> dynamic*/ f();
+}
+
+main() {}