code: private void maybeProcessDomTagName(Node n) {
      if (NodeUtil.isLValue(n)) {
        return;
      }
      String prefix = "goog$dom$TagName$";
      String tagName;
      if (n.isName() && n.getString().startsWith(prefix)) {
        tagName = n.getString().substring(prefix.length());
      } else if (n.isGetProp() && !n.getParent().isGetProp()
          && n.getFirstChild().matchesQualifiedName("goog.dom.TagName")) {
        tagName = n.getSecondChild().getString()
            .replaceFirst(".*\\$", ""); // Added by DisambiguateProperties.
      } else {
        return;
      }
      Node stringNode = IR.string(tagName).srcref(n);
      n.replaceWith(stringNode);
      compiler.reportChangeToEnclosingScope(stringNode);
    }
docs: Converts the given node to string if it is safe to do so.