fix(dart/transformer): Correctly handle const object annotations

Previously, annotations which were const objects (as opposed to const
instance creation expressions) were incorrectly output as instance
creation expressions.

Before:
```
const override() // A const instance creation expression
```

After
```
override // A const instance
```

Closes #4481

modules_dart/transform/lib/src/transform/bind_generator/generator.dart

@@ -50,6 +50,7 @@ class _ExtractQueryFieldsFromPropMetadata extends Object
   bool _hasQueryAnnotation(list) {
     var res = false;
     list.elements.forEach((item) {
+      if (item is! InstanceCreationExpression) return;
       var n = item.constructorName.toString();
       if (n == "ContentChild" ||
           n == "ViewChild" ||

modules_dart/transform/lib/src/transform/common/code/annotation_code.dart

@@ -36,9 +36,12 @@ class AnnotationVisitor extends SimpleAstVisitor<AnnotationModel> {
       ..isComponent = isComponent
       ..isDirective = isDirective
       ..isInjectable = isInjectable
-      ..isView = isView;
+      ..isView = isView
+      ..isConstObject = node.arguments == null;
 
-    if (node.arguments != null) {
+    // This annotation is a constant instance creation expression,
+    // e.g. @Injectable(), rather than a const object, e.g. @override.
+    if (!model.isConstObject) {
       for (var arg in node.arguments.arguments) {
         if (arg is NamedExpression) {
           model.namedParameters.add(new NamedParameter()
@@ -60,7 +63,11 @@ abstract class AnnotationWriterMixin {
   StringBuffer get buffer;
 
   void writeAnnotationModel(AnnotationModel model) {
-    if (model.parameters != null || model.namedParameters != null) {
+    if (model.isConstObject) {
+      // This is a const instance, not a ctor invocation and does not need a
+      // const instance creation expression.
+      buffer.write(model.name);
+    } else {
       buffer.write('const ${model.name}(');
       var first = true;
       for (var param in model.parameters) {
@@ -83,10 +90,6 @@ abstract class AnnotationWriterMixin {
         buffer.write('${param.name}: ${param.value}');
       }
       buffer.write(')');
-    } else {
-      // This is a const instance, not a ctor invocation and does not need a
-      // const instance creation expression.
-      buffer.write(model.name);
     }
   }
 }

modules_dart/transform/lib/src/transform/common/model/annotation_model.pb.dart

@@ -8,67 +8,91 @@ import 'package:protobuf/protobuf.dart';
 class NamedParameter extends GeneratedMessage {
   static final BuilderInfo _i = new BuilderInfo('NamedParameter')
     ..a(1, 'name', PbFieldType.QS)
-    ..a(2, 'value', PbFieldType.QS)
-  ;
+    ..a(2, 'value', PbFieldType.QS);
 
   NamedParameter() : super();
-  NamedParameter.fromBuffer(List<int> i, [ExtensionRegistry r = ExtensionRegistry.EMPTY]) : super.fromBuffer(i, r);
-  NamedParameter.fromJson(String i, [ExtensionRegistry r = ExtensionRegistry.EMPTY]) : super.fromJson(i, r);
+  NamedParameter.fromBuffer(List<int> i,
+      [ExtensionRegistry r = ExtensionRegistry.EMPTY])
+      : super.fromBuffer(i, r);
+  NamedParameter.fromJson(String i,
+      [ExtensionRegistry r = ExtensionRegistry.EMPTY])
+      : super.fromJson(i, r);
   NamedParameter clone() => new NamedParameter()..mergeFromMessage(this);
   BuilderInfo get info_ => _i;
   static NamedParameter create() => new NamedParameter();
-  static PbList<NamedParameter> createRepeated() => new PbList<NamedParameter>();
+  static PbList<NamedParameter> createRepeated() =>
+      new PbList<NamedParameter>();
   static NamedParameter getDefault() {
-    if (_defaultInstance == null) _defaultInstance = new _ReadonlyNamedParameter();
+    if (_defaultInstance == null) _defaultInstance =
+        new _ReadonlyNamedParameter();
     return _defaultInstance;
   }
+
   static NamedParameter _defaultInstance;
   static void $checkItem(NamedParameter v) {
-    if (v is !NamedParameter) checkItemFailed(v, 'NamedParameter');
+    if (v is! NamedParameter) checkItemFailed(v, 'NamedParameter');
   }
 
   String get name => getField(1);
-  void set name(String v) { setField(1, v); }
+  void set name(String v) {
+    setField(1, v);
+  }
+
   bool hasName() => hasField(1);
   void clearName() => clearField(1);
 
   String get value => getField(2);
-  void set value(String v) { setField(2, v); }
+  void set value(String v) {
+    setField(2, v);
+  }
+
   bool hasValue() => hasField(2);
   void clearValue() => clearField(2);
 }
 
-class _ReadonlyNamedParameter extends NamedParameter with ReadonlyMessageMixin {}
+class _ReadonlyNamedParameter extends NamedParameter with ReadonlyMessageMixin {
+}
 
 class AnnotationModel extends GeneratedMessage {
   static final BuilderInfo _i = new BuilderInfo('AnnotationModel')
     ..a(1, 'name', PbFieldType.QS)
     ..p(2, 'parameters', PbFieldType.PS)
-    ..pp(3, 'namedParameters', PbFieldType.PM, NamedParameter.$checkItem, NamedParameter.create)
+    ..pp(3, 'namedParameters', PbFieldType.PM, NamedParameter.$checkItem,
+        NamedParameter.create)
     ..a(4, 'isView', PbFieldType.OB)
     ..a(5, 'isDirective', PbFieldType.OB)
     ..a(6, 'isComponent', PbFieldType.OB)
     ..a(7, 'isInjectable', PbFieldType.OB)
-  ;
+    ..a(8, 'isConstObject', PbFieldType.OB);
 
   AnnotationModel() : super();
-  AnnotationModel.fromBuffer(List<int> i, [ExtensionRegistry r = ExtensionRegistry.EMPTY]) : super.fromBuffer(i, r);
-  AnnotationModel.fromJson(String i, [ExtensionRegistry r = ExtensionRegistry.EMPTY]) : super.fromJson(i, r);
+  AnnotationModel.fromBuffer(List<int> i,
+      [ExtensionRegistry r = ExtensionRegistry.EMPTY])
+      : super.fromBuffer(i, r);
+  AnnotationModel.fromJson(String i,
+      [ExtensionRegistry r = ExtensionRegistry.EMPTY])
+      : super.fromJson(i, r);
   AnnotationModel clone() => new AnnotationModel()..mergeFromMessage(this);
   BuilderInfo get info_ => _i;
   static AnnotationModel create() => new AnnotationModel();
-  static PbList<AnnotationModel> createRepeated() => new PbList<AnnotationModel>();
+  static PbList<AnnotationModel> createRepeated() =>
+      new PbList<AnnotationModel>();
   static AnnotationModel getDefault() {
-    if (_defaultInstance == null) _defaultInstance = new _ReadonlyAnnotationModel();
+    if (_defaultInstance == null) _defaultInstance =
+        new _ReadonlyAnnotationModel();
     return _defaultInstance;
   }
+
   static AnnotationModel _defaultInstance;
   static void $checkItem(AnnotationModel v) {
-    if (v is !AnnotationModel) checkItemFailed(v, 'AnnotationModel');
+    if (v is! AnnotationModel) checkItemFailed(v, 'AnnotationModel');
   }
 
   String get name => getField(1);
-  void set name(String v) { setField(1, v); }
+  void set name(String v) {
+    setField(1, v);
+  }
+
   bool hasName() => hasField(1);
   void clearName() => clearField(1);
 
@@ -77,27 +101,48 @@ class AnnotationModel extends GeneratedMessage {
   List<NamedParameter> get namedParameters => getField(3);
 
   bool get isView => getField(4);
-  void set isView(bool v) { setField(4, v); }
+  void set isView(bool v) {
+    setField(4, v);
+  }
+
   bool hasIsView() => hasField(4);
   void clearIsView() => clearField(4);
 
   bool get isDirective => getField(5);
-  void set isDirective(bool v) { setField(5, v); }
+  void set isDirective(bool v) {
+    setField(5, v);
+  }
+
   bool hasIsDirective() => hasField(5);
   void clearIsDirective() => clearField(5);
 
   bool get isComponent => getField(6);
-  void set isComponent(bool v) { setField(6, v); }
+  void set isComponent(bool v) {
+    setField(6, v);
+  }
+
   bool hasIsComponent() => hasField(6);
   void clearIsComponent() => clearField(6);
 
   bool get isInjectable => getField(7);
-  void set isInjectable(bool v) { setField(7, v); }
+  void set isInjectable(bool v) {
+    setField(7, v);
+  }
+
   bool hasIsInjectable() => hasField(7);
   void clearIsInjectable() => clearField(7);
+
+  bool get isConstObject => getField(8);
+  void set isConstObject(bool v) {
+    setField(8, v);
+  }
+
+  bool hasIsConstObject() => hasField(8);
+  void clearIsConstObject() => clearField(8);
 }
 
-class _ReadonlyAnnotationModel extends AnnotationModel with ReadonlyMessageMixin {}
+class _ReadonlyAnnotationModel extends AnnotationModel
+    with ReadonlyMessageMixin {}
 
 const NamedParameter$json = const {
   '1': 'NamedParameter',
@@ -112,17 +157,24 @@ const AnnotationModel$json = const {
   '2': const [
     const {'1': 'name', '3': 1, '4': 2, '5': 9},
     const {'1': 'parameters', '3': 2, '4': 3, '5': 9},
-    const {'1': 'named_parameters', '3': 3, '4': 3, '5': 11, '6': '.angular2.src.transform.common.model.proto.NamedParameter'},
+    const {
+      '1': 'named_parameters',
+      '3': 3,
+      '4': 3,
+      '5': 11,
+      '6': '.angular2.src.transform.common.model.proto.NamedParameter'
+    },
     const {'1': 'is_view', '3': 4, '4': 1, '5': 8},
     const {'1': 'is_directive', '3': 5, '4': 1, '5': 8},
     const {'1': 'is_component', '3': 6, '4': 1, '5': 8},
     const {'1': 'is_injectable', '3': 7, '4': 1, '5': 8},
+    const {'1': 'is_const_object', '3': 8, '4': 1, '5': 8},
   ],
 };
 
 /**
  * Generated with:
- * annotation_model.proto (5ca037df4c4d3e5d2771a177c9f5ea9dc8ae5f91)
+ * annotation_model.proto (93cb7c1fba2e56d937fec054b6e119a2a2b9afe7)
  * libprotoc 2.5.0
  * dart-protoc-plugin (cc35f743de982a4916588b9c505dd21c7fe87d17)
  */

modules_dart/transform/lib/src/transform/common/model/annotation_model.proto

@@ -25,11 +25,16 @@ message AnnotationModel {
   // account, that is, this should be true if `is_component` is true.
   optional bool is_directive = 5;
 
-  // Whether htis is a `Component` annotation.
+  // Whether this is a `Component` annotation.
   optional bool is_component = 6;
 
   // Whether this is an `Injectable` annotation. This takes inheritance into
   // account, that is, this should be true if `is_directive` and/or
   // `is_component` is true.
   optional bool is_injectable = 7;
+
+  // Whether this annotation is a constant object (for example, `@override`) as
+  // opposed to a const instance creation expression
+  // (for example, `@Injectable()`).
+  optional bool is_const_object = 8;
 }