Implement vtable helper stubs
diff --git a/src/core/client_config/lb_policy.h b/src/core/client_config/lb_policy.h
index 0b21af4..4e185d9 100644
--- a/src/core/client_config/lb_policy.h
+++ b/src/core/client_config/lb_policy.h
@@ -44,6 +44,10 @@
typedef void (*grpc_lb_completion)(void *cb_arg, grpc_subchannel *subchannel,
grpc_status_code status, const char *errmsg);
+struct grpc_lb_policy {
+ grpc_lb_policy_vtable *vtable;
+};
+
struct grpc_lb_policy_vtable {
void (*ref)(grpc_lb_policy *policy);
void (*unref)(grpc_lb_policy *policy);