Add isParameter, change isField to isVariable on MemberMirror

sdk/lib/_internal/dartdoc/lib/src/mirrors/dart2js_mirror.dart

Index: sdk/lib/_internal/dartdoc/lib/src/mirrors/dart2js_mirror.dart
diff --git a/sdk/lib/_internal/dartdoc/lib/src/mirrors/dart2js_mirror.dart b/sdk/lib/_internal/dartdoc/lib/src/mirrors/dart2js_mirror.dart
index 551eedad5562258d6c428eed696c299cb4b47495..a28bb7ff3aa628f1e8bd7147863e4c3e168f23f7 100644
--- a/sdk/lib/_internal/dartdoc/lib/src/mirrors/dart2js_mirror.dart
+++ b/sdk/lib/_internal/dartdoc/lib/src/mirrors/dart2js_mirror.dart
@@ -404,11 +404,13 @@ abstract class Dart2JsMemberMirror extends Dart2JsElementMirror
 
   bool get isConstructor => false;
 
-  bool get isField => false;
+  bool get isVariable => false;
 
   bool get isMethod => false;
 
   bool get isStatic => false;
+
+  bool get isParameter => false;
 }
 
 abstract class Dart2JsTypeMirror extends Dart2JsDeclarationMirror
@@ -1506,7 +1508,7 @@ class Dart2JsFieldMirror extends Dart2JsMemberMirror implements VariableMirror {
 
   bool get isTopLevel => _objectMirror is LibraryMirror;
 
-  bool get isField => true;
+  bool get isVariable => true;
 
   bool get isStatic => _variable.modifiers.isStatic();