Fuse top level type inference with dependency generation.

pkg/front_end/testcases/inference_new/dependency_only_if_overloaded.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;
+
+int intValue = 0;
+num numValue = 0;
+double doubleValue = 0.0;
+
+// There's a circularity between a and b because the type of `int + x` depends
+// on the type of x.
+
+var /*@topType=dynamic*/ a = /*@returnType=num*/ () =>
+    intValue /*@target=num::+*/ + b;
+var /*@topType=dynamic*/ b = a();
+
+// But there's no circularity between c and d because the type of `num + x` is
+// always num.
+
+var /*@topType=() -> num*/ c = /*@returnType=num*/ () =>
+    numValue /*@target=num::+*/ + d;
+var /*@topType=num*/ d = c();
+
+// Similar for double.
+
+var /*@topType=() -> double*/ e = /*@returnType=double*/ () =>
+    doubleValue /*@target=double::+*/ + f;
+var /*@topType=double*/ f = e();
+
+main() {}