Perform type inference on constructor field initializer expressions.

pkg/front_end/testcases/inference/bug30251.dart

Index: pkg/front_end/testcases/inference/bug30251.dart
diff --git a/pkg/front_end/testcases/inference/bug30251.dart b/pkg/front_end/testcases/inference/bug30251.dart
new file mode 100644
index 0000000000000000000000000000000000000000..63e0ffa72989b4ed46e041067f3ab30d68bc5296
--- /dev/null
+++ b/pkg/front_end/testcases/inference/bug30251.dart
@@ -0,0 +1,15 @@
+// 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;
+
+T f<T>(T t) => t;
+
+class C {
+  final /*@topType=dynamic*/ x;
+  C(int p) : x = /*@typeArgs=int*/ f(1 /*@target=num::+*/ + p);
+}
+
+main() {}