Inline MethodMirror creation

runtime/lib/mirrors_impl.dart

Index: runtime/lib/mirrors_impl.dart
diff --git a/runtime/lib/mirrors_impl.dart b/runtime/lib/mirrors_impl.dart
index d957cc771bc11f793d37311e382d9de772870239..1ad1707826580afc9fe6f80b1a38f79882c2ac20 100644
--- a/runtime/lib/mirrors_impl.dart
+++ b/runtime/lib/mirrors_impl.dart
@@ -890,7 +890,6 @@ class _LocalMethodMirrorImpl extends _LocalDeclarationMirrorImpl
     implements MethodMirror {
   _LocalMethodMirrorImpl(reflectee,
                          this._owner,
-                         this.parameters,
                          this.isStatic,
                          this.isAbstract,
                          this.isGetter,
@@ -955,7 +954,13 @@ class _LocalMethodMirrorImpl extends _LocalDeclarationMirrorImpl
     return _returnType;
   }
 
-  final List<ParameterMirror> parameters;
+  List<ParameterMirror> _parameters = null;
+  List<ParameterMirror> get parameters {
+    if (_parameters == null) {
+      _parameters = _MethodMirror_parameters(_reflectee);
+    }
+    return _parameters;
+  }
 
   final bool isStatic;
   final bool isAbstract;
@@ -1007,6 +1012,9 @@ class _LocalMethodMirrorImpl extends _LocalDeclarationMirrorImpl
 
   static dynamic _MethodMirror_return_type(reflectee)
       native "MethodMirror_return_type";
+
+  static List<MethodMirror> _MethodMirror_parameters(reflectee)
+      native "MethodMirror_parameters";
 }
 
 class _LocalVariableMirrorImpl extends _LocalDeclarationMirrorImpl