Mojo C++ bindings: sync call support for associated interfaces and master interfaces

mojo/public/cpp/bindings/lib/binding_state.h

Index: mojo/public/cpp/bindings/lib/binding_state.h
diff --git a/mojo/public/cpp/bindings/lib/binding_state.h b/mojo/public/cpp/bindings/lib/binding_state.h
index feef835be10fa89802fb2558fff4e44faac61fab..b3588da724e81ae2485398e29000fa48e260eea3 100644
--- a/mojo/public/cpp/bindings/lib/binding_state.h
+++ b/mojo/public/cpp/bindings/lib/binding_state.h
@@ -149,7 +149,8 @@ class BindingState<Interface, true> {
 
     endpoint_client_.reset(new internal::InterfaceEndpointClient(
         router_->CreateLocalEndpointHandle(internal::kMasterInterfaceId),
-        &stub_, make_scoped_ptr(new typename Interface::RequestValidator_())));
+        &stub_, make_scoped_ptr(new typename Interface::RequestValidator_()),
+        Interface::HasSyncMethods_));
 
     endpoint_client_->set_connection_error_handler(
         [this]() { connection_error_handler_.Run(); });