Support root-level json rpc requests in the vm service.

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

Index: runtime/observatory/lib/src/service/object.dart
diff --git a/runtime/observatory/lib/src/service/object.dart b/runtime/observatory/lib/src/service/object.dart
index e2030a217ccdef35e723205abcdc79b07b28ff25..234e281dc3ae95f56e39a32721aa5897062772f2 100644
--- a/runtime/observatory/lib/src/service/object.dart
+++ b/runtime/observatory/lib/src/service/object.dart
@@ -211,6 +211,13 @@ abstract class ServiceObject extends Observable {
 
   Future<ServiceObject> _inProgressReload;
 
+  Future<ObservableMap> _fetchDirect() {
+    Map params = {
+      'objectId': id,
+    };
+    return isolate.invokeRpcNoUpgrade('getObject', params);
+  }
+
   /// Reload [this]. Returns a future which completes to [this] or
   /// a [ServiceError].
   Future<ServiceObject> reload() {
@@ -223,7 +230,7 @@ abstract class ServiceObject extends Observable {
       return new Future.value(this);
     }
     if (_inProgressReload == null) {
-      _inProgressReload = vm.getAsMap(link).then((ObservableMap map) {
+      _inProgressReload = _fetchDirect().then((ObservableMap map) {
           var mapType = _stripRef(map['type']);
           if (mapType != _type) {
             // If the type changes, return a new object instead of
@@ -589,6 +596,10 @@ abstract class VM extends ServiceObjectOwner {
     });
   }
 
+  Future<ObservableMap> _fetchDirect() {
+    return invokeRpcNoUpgrade('getVM', {});
+  }
+
   /// Force the VM to disconnect.
   void disconnect();
   /// Completes when the VM first connects.
@@ -909,7 +920,6 @@ class Isolate extends ServiceObjectOwner with Coverage {
     return vm.invokeRpcNoUpgrade(method, params);
   }
 
-
   Future<ServiceObject> invokeRpc(String method, Map params) {
     return invokeRpcNoUpgrade(method, params).then((ObservableMap response) {
       // TODO - needs to cache!!! move to constructor?
@@ -917,6 +927,10 @@ class Isolate extends ServiceObjectOwner with Coverage {
     });
   }
 
+  Future<ObservableMap> _fetchDirect() {
+    return invokeRpcNoUpgrade('getIsolate', {});
+  }
+
   @observable Class objectClass;
   @observable final rootClasses = new ObservableList<Class>();
 
@@ -2797,6 +2811,12 @@ class ServiceMetric extends ServiceObject {
     _removeOld();
   }
 
+  Future<ObservableMap> _fetchDirect() {
+    // TODO(johnmmccutchan): Make this use json rpc.
+    return vm.getAsMap(link);
+  }
+
+
   void addSample(MetricSample sample) {
     samples.add(sample);
     _removeOld();