fix feature reading

src/wasm/wasm-binary.cpp

@@ -5195,6 +5195,8 @@ void WasmBinaryReader::readFeatures(size_t payloadLen) {
       feature = FeatureSet::FP16;
     } else if (name == BinaryConsts::CustomSections::CustomDescriptorsFeature) {
       feature = FeatureSet::CustomDescriptors;
+    } else if (name == BinaryConsts::CustomSections::StringBuiltinsFeature) {
+      feature = FeatureSet::StringBuiltins;
     } else {
       // Silently ignore unknown features (this may be and old binaryen running
       // on a new wasm).