Always returns a ParamBag

[bburnichon]

Having to check whether there is a ParamBag or not is error prone.

This PR ensures Transformers are always called with a ParamBag instance.

[bburnichon]

ping @willishq @jasonlewis @philsturgeon

[hskrasek]

I was about to open a PR for this, but looks like someone else beat me to it. Would help removing the extra $params === null check that can make include logic odd, depending on how you use include params

[philsturgeon]

@bburnichon could you implement what @hskrasek suggested? @greydnls will be able to pick this up when back from the PHP Cruise :D

[bburnichon]

@philsturgeon I don't understand what you want me to implement. The extra $params === null check is not in library code, but on each include method of TransformerAbstract subclasses.

[philsturgeon]

I'm just asking if you have a response to @hskrasek's suggestion. Work it out amongst yourselves. :)

[bburnichon]

So yes, merge the PR and it will do what @hskrasek wants to achieve 😄. Am I wrong, @hskrasek?

[hskrasek]

Yea sorry, my wording might have been off. I was honestly just bumping this PR since it would be useful. So you're all good @bburnichon, PR just needs to be merged if it looks good to @greydnls.