[R] Wire up dplyr::mutate() for datasets

[asfimport]

https://github.com/apache/arrow/pull/9532/files#diff-621536af77a522e4dd62ede27eba1da5ab533dc6565140c498f86824b25b8cb3R209:

  /// \brief Set expressions which will be evaluated to produce the materialized columns.
  ///
  /// Columns which are not referenced may not be loaded from disk.
  ///
  /// \param[in] exprs expressions to evaluate to produce columns.
  /// \param[in] names list of names for the resulting columns.
  ///
  /// \return Failure if any referenced column does not exists in the dataset's
  ///         Schema.
  Status Project(std::vector<Expression> exprs, std::vector<std::string> names);

Reporter: Neal Richardson / @nealrichardson
Assignee: Neal Richardson / @nealrichardson

Related issues:

• [C++][Dataset] Make Expressions available for projection (depends upon)
• [R] Support dplyr::mutate() (depends upon)

PRs and other links:

• GitHub Pull Request #9586

_{Note: This issue was originally created as ARROW-11704. Please see the migration documentation for further details.}

[asfimport]

Neal Richardson / @nealrichardson:
Issue resolved by pull request 9586
#9586