Add ParameterMirror.isInitializingFormal to dart:mirrors

pkg/compiler/lib/src/js_emitter/full_emitter/container_builder.dart

Index: pkg/compiler/lib/src/js_emitter/full_emitter/container_builder.dart
diff --git a/pkg/compiler/lib/src/js_emitter/full_emitter/container_builder.dart b/pkg/compiler/lib/src/js_emitter/full_emitter/container_builder.dart
index ebd7d1a1d2ad9df200e6962dcb69a28746240474..ac95afc4e8600624d07c58cf575fde30bd03698b 100644
--- a/pkg/compiler/lib/src/js_emitter/full_emitter/container_builder.dart
+++ b/pkg/compiler/lib/src/js_emitter/full_emitter/container_builder.dart
@@ -67,8 +67,11 @@ class ContainerBuilder extends CodeEmitterHelper {
     // ...
     // O.   First parameter name (if needed for reflection or Function.apply).
     // ...
-    // P.   Unmangled name (if reflectable).
-    // P+1. First metadata (if reflectable).
+    // P. Whether the first argument is field initialization parameter
+    //      (if reflectable and a constructor)
+    // ...
+    // Q.   Unmangled name (if reflectable).
+    // Q+1. First metadata (if reflectable).
     // ...
     // TODO(ahe): Consider one of the parameter counts can be replaced by the
     // length property of the JavaScript function object.
@@ -151,7 +154,10 @@ class ContainerBuilder extends CodeEmitterHelper {
     }
     if (canBeReflected) {
       jsAst.LiteralString reflectionName;
+      List<jsAst.LiteralBool> argumentsInstantiatingFields = new List();
       if (member.isConstructor) {
+        member.functionSignature.forEachParameter((element) =>
+          argumentsInstantiatingFields.add(js.boolean(element is InitializingFormalElement)));
         // TODO(herhut): This registers name as a mangled name. Do we need this
         //               given that we use a different name below?
         emitter.getReflectionName(member, name);
@@ -161,8 +167,11 @@ class ContainerBuilder extends CodeEmitterHelper {
       } else {
         reflectionName =
             js.string(namer.privateName(member.memberName));
+        member.functionSignature.forEachParameter((element) =>
+          argumentsInstantiatingFields.add(js.boolean(false)));
       }
       expressions
+          ..addAll(argumentsInstantiatingFields)
           ..add(reflectionName)
           ..addAll(task.metadataCollector.computeMetadata(member));
     } else if (isClosure && canBeApplied) {