Add Sync data type for managed users.

sync/internal_api/public/base_node.h

Index: sync/internal_api/public/base_node.h
diff --git a/sync/internal_api/public/base_node.h b/sync/internal_api/public/base_node.h
index 7cf2edb2af257ab15ebf97cb2afaa13afeccf5e9..3c56b5ebe18e1b13c1ca947b914bea93c48a5435 100644
--- a/sync/internal_api/public/base_node.h
+++ b/sync/internal_api/public/base_node.h
@@ -158,6 +158,10 @@ class SYNC_EXPORT BaseNode {
   const sync_pb::ManagedUserSettingSpecifics&
       GetManagedUserSettingSpecifics() const;
 
+  // Getter specific to the MANAGED_USERS datatype.  Returns protobuf data.
+  // Can only be called if GetModelType() == MANAGED_USERS.
+  const sync_pb::ManagedUserSpecifics& GetManagedUserSpecifics() const;
+
   // Getter specific to the DEVICE_INFO datatype.  Returns protobuf
   // data.  Can only be called if GetModelType() == DEVICE_INFO.
   const sync_pb::DeviceInfoSpecifics& GetDeviceInfoSpecifics() const;