message: Fix the JNI local ref overflow issue.
diff: @@ -50,6 +50,9 @@ jobject ConvertToCategory(JNIEnv* env, const Class& classification) {
  jobject jcategory =
  env->CallStaticObjectMethod(category_class, category_create, label,
  display_name, classification.score());
  + env->DeleteLocalRef(category_class);
  + env->DeleteLocalRef(label);
  + env->DeleteLocalRef(display_name);
  return jcategory;
  }
  