Add `=` as default-value separator for named parameters.

tests/language/named_parameters_default_eq_test.dart

+// Copyright (c) 2016, 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.
+
+// Check that both `=` and `:` are allowed for named parameters.
+
+import "package:expect/expect.dart";
+
+// Default values are not allowed on typedefs.
+typedef int F1({x = 3, y}); /// 01: compile-time error
+
+typedef int functype({x, y, z});
+
+int topF({x = 3, y : 5, z}) => x * y * (z ?? 2);
+
+class A {
+  int x;
+  int y;
+  int z;
+  A({this.x = 3, this.y : 5, z }) : z = z ?? 2;
+  A.redirect({x = 3, y : 5, z}) : this(x: x, y: y, z: z);
+  factory A.factory({x = 3, y : 5, z}) => new A(x: x, y: y, z: z ?? 2);
+  factory A.redirectFactory({x, y, z}) = A;
+
+  // Default values are not allowed on redirecting factory constructors.
+  factory A.badRedirectFactory({x = 3, y}) = A; /// 02: compile-time error
+
+  int get value => x * y * z;
+
+  static int staticF({x = 3, y : 5, z}) => x * y * (z ?? 2);
+  int instanceF({x = 3, y : 5, z}) => x * y * (z ?? 2);
+}
+
+main() {
+  var a = new A();
+
+  int local({x = 3, y : 5, z}) => x * y * (z ?? 2);
+  var expr = ({x = 3, y : 5, z}) => x * y * (z ?? 2);
+  var tearOff = a.instanceF;
+
+  test(function) {
+    Expect.equals(30, function());
+    Expect.equals(70, function(x: 7));
+    Expect.equals(42, function(y: 7));
+    Expect.equals(28, function(x: 7, y: 2));
+    Expect.equals(15, function(z: 1));
+    Expect.equals(21, function(y: 7, z: 1));
+    Expect.equals(35, function(x: 7, z: 1));
+    Expect.equals(14, function(x: 7, y: 2, z: 1));
+    Expect.isTrue(function is functype);
+  }
+
+  test(topF);
+  test(A.staticF);
+  test(a.instanceF);
+  test(local);
+  test(expr);
+  test(tearOff);
+
+  // Can't tear off constructors.
+  Expect.equals(30, new A().value);
+  Expect.equals(70, new A(x: 7).value);
+  Expect.equals(42, new A(y: 7).value);
+  Expect.equals(28, new A(x: 7, y: 2).value);
+  Expect.equals(15, new A(z: 1).value);
+  Expect.equals(21, new A(y: 7, z: 1).value);
+  Expect.equals(35, new A(x: 7, z: 1).value);
+  Expect.equals(14, new A(x: 7, y: 2, z: 1).value);
+
+  Expect.equals(30, new A.redirect().value);
+  Expect.equals(70, new A.redirect(x: 7).value);
+  Expect.equals(42, new A.redirect(y: 7).value);
+  Expect.equals(28, new A.redirect(x: 7, y: 2).value);
+  Expect.equals(15, new A.redirect(z: 1).value);
+  Expect.equals(21, new A.redirect(y: 7, z: 1).value);
+  Expect.equals(35, new A.redirect(x: 7, z: 1).value);
+  Expect.equals(14, new A.redirect(x: 7, y: 2, z: 1).value);
+
+  Expect.equals(30, new A.factory().value);
+  Expect.equals(70, new A.factory(x: 7).value);
+  Expect.equals(42, new A.factory(y: 7).value);
+  Expect.equals(28, new A.factory(x: 7, y: 2).value);
+  Expect.equals(15, new A.factory(z: 1).value);
+  Expect.equals(21, new A.factory(y: 7, z: 1).value);
+  Expect.equals(35, new A.factory(x: 7, z: 1).value);
+  Expect.equals(14, new A.factory(x: 7, y: 2, z: 1).value);
+
+  Expect.equals(30, new A.redirectFactory().value);
+  Expect.equals(70, new A.redirectFactory(x: 7).value);
+  Expect.equals(42, new A.redirectFactory(y: 7).value);
+  Expect.equals(28, new A.redirectFactory(x: 7, y: 2).value);
+  Expect.equals(15, new A.redirectFactory(z: 1).value);
+  Expect.equals(21, new A.redirectFactory(y: 7, z: 1).value);
+  Expect.equals(35, new A.redirectFactory(x: 7, z: 1).value);
+  Expect.equals(14, new A.redirectFactory(x: 7, y: 2, z: 1).value);
+}