Revert "Give instances their own model class; move DartErrors out of instance-ref into their own er…

runtime/bin/vmservice/observatory/lib/src/service/object.dart

Index: runtime/bin/vmservice/observatory/lib/src/service/object.dart
diff --git a/runtime/bin/vmservice/observatory/lib/src/service/object.dart b/runtime/bin/vmservice/observatory/lib/src/service/object.dart
index 78d29702c4e608a24253bff04931e67260858a78..bc57bb6647b0587397739c14a0ecced4c2a44ed5 100644
--- a/runtime/bin/vmservice/observatory/lib/src/service/object.dart
+++ b/runtime/bin/vmservice/observatory/lib/src/service/object.dart
@@ -34,17 +34,6 @@ abstract class ServiceObject extends Observable {
   @reflectable String get serviceType => _serviceType;
   String _serviceType;
 
-  bool get isBool => serviceType == 'Bool';
-  bool get isDouble => serviceType == 'Double';
-  bool get isError => serviceType == 'Error';
-  bool get isInstance => serviceType == 'Instance';
-  bool get isInt => serviceType == 'Smi' || serviceType == 'Mint' || serviceType == 'Bigint';
-  bool get isList => serviceType == 'GrowableObjectArray' || serviceType == 'Array';
-  bool get isNull => serviceType == 'Null';
-  bool get isSentinel => serviceType == 'Sentinel';
-  bool get isString => serviceType == 'String';
-  bool get isType => serviceType == 'Type';
-
   /// The complete service url of this object.
   @reflectable String get link => _owner.relativeLink(_id);
 
@@ -99,20 +88,6 @@ abstract class ServiceObject extends Observable {
       case 'Gauge':
         obj = new ServiceMetric._empty(owner);
         break;
-      case 'Array':
-      case 'Bigint':
-      case 'Bool':
-      case 'Double':
-      case 'GrowableObjectArray':
-      case 'Instance':
-      case 'Mint':
-      case 'Null':
-      case 'Sentinel':  // TODO(rmacnak): Separate this out.
-      case 'Smi':
-      case 'String':
-      case 'Type':
-        obj = new Instance._empty(owner);
-        break;
       case 'Isolate':
         obj = new Isolate._empty(owner.vm);
         break;
@@ -1184,7 +1159,7 @@ class DartError extends ServiceObject {
 
   @observable String kind;
   @observable String message;
-  @observable Instance exception;
+  @observable ServiceMap exception;
   @observable ServiceMap stacktrace;
 
   void _update(ObservableMap map, bool mapIsRef) {
@@ -1464,54 +1439,6 @@ class Class extends ServiceObject with Coverage {
   String toString() => 'Class($vmName)';
 }
 
-class Instance extends ServiceObject {
-  @observable Class clazz;
-  @observable String valueAsString;
-  @observable int size;
-  @observable ServiceFunction closureFunc;  // If a closure.
-  @observable String name;  // If a Type.
-
-  @observable var typeClass;
-  @observable var length;
-  @observable var fields;
-  @observable var nativeFields;
-  @observable var elements;
-  @observable var userName;
-
-  bool get isClosure => closureFunc != null;
-
-  Instance._empty(ServiceObjectOwner owner) : super._empty(owner);
-
-  void _update(ObservableMap map, bool mapIsRef) {
-    // Extract full properties.
-    _upgradeCollection(map, isolate);
-
-    clazz = map['class'];
-    valueAsString = map['valueAsString'];
-    size = map['size'];
-    closureFunc = map['closureFunc'];
-    name = map['name'];
-
-    if (mapIsRef) {
-      return;
-    }
-
-    nativeFields = map['nativeFields'];
-    fields = map['fields'];
-    length = map['length'];
-    elements = map['elements'];
-    typeClass = map['type_class'];
-    userName = map['user_name'];
-
-    // We are fully loaded.
-    _loaded = true;
-  }
-
-  String get shortName => valueAsString != null ? valueAsString : 'a ${clazz.name}';
-
-  String toString() => 'Instance($shortName)';
-}
-
 // TODO(koda): Sync this with VM.
 class FunctionKind {
   final String _strValue;
@@ -2429,7 +2356,8 @@ class MetricPoller {
 
 // Convert any ServiceMaps representing a null instance into an actual null.
 _convertNull(obj) {
-  if (obj.isNull) {
+  if (obj is ServiceMap &&
+      obj.serviceType == 'Null') {
     return null;
   }
   return obj;