Call processor in visit_item for FUNC_ITEM

[dveeden]

The use case:
Be able to use a post-parse plugin that acts on specific functions being called.

This is done by just adding FUNC_ITEM to the list.
However multiple comments seem to indicate that visit function is only called for literals.

The solutions I see are:

1. Splitting this into two processor functions, one for literals and one for functions. However parse_node_visit_function etc. have generic names, so to make this clean these then have to be renamed to something like pare_node_visit_literal_function etc.
2. Keep this in one processor, but allow one to get the type of the item, this allows one to filter out FUNC_ITEM and any other item when needed. That's what is in this pull request.

Please let me know if you think this is a good solution or if there is a better or cleaner solution.

[mysql-oca-bot]

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Thanks

[dveeden]

I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.

…

On March 4, 2019 13:50:49 mysql-oca-bot ***@***.***> wrote: Hi, thank you for your contribution. Please confirm this code is submitted under the terms of the OCA (Oracle's Contribution Agreement) you have previously signed by cutting and pasting the following text as a comment: "I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it." Thanks— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

[mysql-oca-bot]

Hi, thank you for your contribution. Your code has been assigned to an internal queue. Please follow
bug http://bugs.mysql.com/bug.php?id=94551 for updates.
Thanks