docs: public static Matcher<StatementTree> expressionStatement(final Matcher<ExpressionTree> matcher) {
      return new Matcher<StatementTree>() {
        @Override
        public boolean matches(StatementTree statementTree, VisitorState state) {
          return statementTree instanceof ExpressionStatementTree
              && matcher.matches(((ExpressionStatementTree) statementTree).getExpression(), state);
        }
      };
    }