Add ParameterMirror.isInitializingFormal to dart:mirrors

tests/lib/mirrors/parameter_test.dart

Index: tests/lib/mirrors/parameter_test.dart
diff --git a/tests/lib/mirrors/parameter_test.dart b/tests/lib/mirrors/parameter_test.dart
index 4eb6ad596432523ba8d400ee2f55e28872861e2b..497447cadc89ba69e08580b965e0288254c1c9d7 100644
--- a/tests/lib/mirrors/parameter_test.dart
+++ b/tests/lib/mirrors/parameter_test.dart
@@ -27,8 +27,10 @@ class B {
   B.qux(int x, [int y= 3 + 1]);
   B.quux(int x, {String str: "foo"});
   B.corge({int x: 3 * 17, String str: "bar"});
+  B.corgi(int this.z);
 
   var _x;
+  var z;
   get x =>  _x;
   set x(final value) { _x = value; }
 
@@ -51,7 +53,7 @@ main() {
   });
 
   List<Symbol> constructorKeys =
-      [#B, #B.bar, #B.baz, #B.foo, #B.quux, #B.qux, #B.corge];
+      [#B, #B.bar, #B.baz, #B.foo, #B.quux, #B.qux, #B.corge, #B.corgi];
   Expect.setEquals(constructorKeys, constructors.keys);
 
   MethodMirror unnamedConstructor = constructors[#B];
@@ -127,6 +129,14 @@ main() {
   expect('Class(s(B) in s(test.parameter_test), top-level)',
          corgeConstructor.returnType);
 
+  ParameterMirror bazZParameter = 
+      bazConstructor.parameters.firstWhere((p) => p.simpleName == #z);
+  Expect.isFalse(bazZParameter.isInitializingFormal);
+  MethodMirror corgiConstructor = constructors[#B.corgi];
+  ParameterMirror corgiZParameter = 
+      corgiConstructor.parameters.firstWhere((p) => p.simpleName == #z);
+  Expect.isTrue(corgiZParameter.isInitializingFormal);
+
   MethodMirror xGetter = cm.declarations[#x];
   expect('Method(s(x) in s(B), getter)', xGetter);
   expect('[]', xGetter.parameters);