bluetoothLowEnergy: Send onServiceAdded after all characteristics are discovered

chromeos/dbus/bluetooth_gatt_service_client.h

Index: chromeos/dbus/bluetooth_gatt_service_client.h
diff --git a/chromeos/dbus/bluetooth_gatt_service_client.h b/chromeos/dbus/bluetooth_gatt_service_client.h
index d3ed19d23e5eb600a760411f15bd13906cf2692f..36d212379740e8af1482309ba5293b3cd4d934b9 100644
--- a/chromeos/dbus/bluetooth_gatt_service_client.h
+++ b/chromeos/dbus/bluetooth_gatt_service_client.h
@@ -30,6 +30,10 @@ class CHROMEOS_EXPORT BluetoothGattServiceClient : public DBusClient {
     // Whether or not this service is a primary service.
     dbus::Property<bool> primary;
 
+    // Array of object paths representing the characteristics of this service.
+    // [read-only]
+    dbus::Property<std::vector<dbus::ObjectPath> > characteristics;
+
     // Array of object paths representing the included services of this service.
     // [read-only]
     dbus::Property<std::vector<dbus::ObjectPath> > includes;