message: Fix issue when no context_free_data
diff: @@ -340,10 +340,11 @@ namespace impl {
  static void extract( const variant& v, packed_transaction& ptrx, Resolver resolver ) {
  const variant_object& vo = v.get_object();
  FC_ASSERT(vo.contains("signatures"));
  - FC_ASSERT(vo.contains("context_free_data"));
  FC_ASSERT(vo.contains("compression"));
  from_variant(vo["signatures"], ptrx.signatures);
  + if ( vo.contains("context_free_data")) {
  from_variant(vo["context_free_data"], ptrx.context_free_data);
  + }
  from_variant(vo["compression"], ptrx.compression);
  if (vo.contains("hex_data") && vo["hex_data"].is_string() && !vo["hex_data"].as_string().empty()) {
  