[Forwardport] Fix for Magnifier in inside mode

[torhoehn]

Original Pull Request

#15382

Fixed Issues

1. Magnifier doesn't work with mode set to inner #4977: Magnifier doesn't work with mode set to inner

Manual testing scenarios

You need to change the magnifier's configuration options in the file: app/design/frontend/Magento/luma/etc/view.xml

Set the following values ​​for these lines:

<var name="enabled">true</var>
<var name="mode">inside</var>

[magento-engcom-team]

Hi @torhoehn. Thank you for your contribution
Here is some useful tips how you can test your changes using Magento test environment.
Add the comment under your pull request to deploy test or vanilla Magento instance:

• @magento-engcom-team give me test instance - deploy test instance based on PR changes
• @magento-engcom-team give me {$VERSION} instance - deploy vanilla Magento instance

For more details, please, review the Magento Contributor Assistant documentation

[magento-engcom-team]

Hi @ihor-sviziev, thank you for the review.
ENGCOM-2505 has been created to process this Pull Request

[magento-engcom-team]

Hi @torhoehn. Thank you for your contribution.
We will aim to release these changes as part of 2.3.0.
Please check the release notes for final confirmation.