static @Nullable Icon getKeyValueIcon(@NotNull YAMLKeyValue kv) {
    YAMLValue value = kv.getValue();
    if (value instanceof YAMLScalar) {
      return kv.getIcon(0);
    }
    else if (value instanceof YAMLAlias) {
      return ALIAS_ICON;
    }
    else {
      return PlatformIcons.XML_TAG_ICON;
    }
  }
static @Nullable Icon getKeyValueIcon(@NotNull YAMLKeyValue kv)