code: public static SanitizedContent constantHtml(@CompileTimeConstant final String constant) {
      return fromConstant(constant, ContentKind.HTML, null);
    }
docs: Wraps an assumed-safe constant string that specifies a safe, balanced, document fragment.
  
  <p>This only accepts compile-time constants, based on the assumption that HTML snippets that
  are controlled by the application (and not user input) are considered safe.