Create ability to set is_visible_on_front to order status history comment

[markshust]

Create ability to set is_visible_on_front to order status history comment.

Description

The parameter is_visible_on_front is able to be set from the admin, but not from addStatusHistoryComment of the order model. This would provide the ability to set this value from custom code such as event observers.

Manual testing scenarios

1. Call ->addStatusHistoryComment($comment, false) to not set is_visible_on_front (backwards compatible with no extra param)
2. Call ->addStatusHistoryComment($comment, false, true) to set is_visible_on_front
3. Call ->addStatusHistoryComment($comment, false, false) to not set is_visible_on_front

Contribution checklist

• [x ] Pull request has a meaningful description of its purpose
• [x ] All commits are accompanied by meaningful commit messages
• [x ] All new or changed code is covered with unit/integration tests (if applicable)
• [x ] All automated tests passed successfully (all builds on Travis CI are green)

[magento-cicd2]

All committers have signed the CLA.

[magento-engcom-team]

@markoshust thank you for contributing. Please accept Community Contributors team invitation here to gain extended permissions for this repository.

[dmanners]

Thanks for this PR @markoshust I will start to process this for you now.

[magento-engcom-team]

Hi @markoshust. Thank you for your contribution.
Changes from your Pull Request will be available with the upcoming 2.2.6 release.

Please, consider to port this solution to 2.3 release line.
You may use Porting tool to port commits automatically.

[markshust]

i just had a quick question on how new releases work. it looks like the 2.2.6 branch is not re-merged into 2.3? so, any updates that are not separately merged into 2.3 are lost?

[torhoehn]

@markoshust If a change has to be in 2.2.6 and 2.3 you have to create a Forwardport after it has been merged to 2.2-develop. The Porting Tool will help you doing this.