Fixed critical error 'Undefined constant formName'

[cpini]

Description (*)

Getting an 'undefined constant formName' error in the Admin panel when trying to edit products so just fixed the place in the template where this was happening - simple fix.
Stack: Alpine/Apache 2.4/PHP7.2.1 (+FPM)

Single file change: app/code/Magento/Catalog/view/adminhtml/templates/catalog/product/helper/gallery.phtml

Manual testing scenarios (*)

1. Admin > Catalog > Product then click on product to edit - previously error was being thrown and crashing the page now the product is editable.

Contribution checklist (*)

• Pull request has a meaningful description of its purpose - yes
• All commits are accompanied by meaningful commit messages - yes
• All new or changed code is covered with unit/integration tests - n/a
• All automated tests passed successfully - ok, see output below

./vendor/bin/phpunit -d memory_limit=1200M -c dev/tests/unit/phpunit.xml.dist app/code/Magento/Catalog/Test
PHPUnit 6.5.14 by Sebastian Bergmann and contributors.
Time: 41.95 seconds, Memory: 170.25MB
OK, but incomplete, skipped, or risky tests!
Tests: 1573, Assertions: 4884, Skipped: 26, Incomplete: 2.

[m2-assistant]

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[magento-cicd2]

All committers have signed the CLA.

[magento-engcom-team]

Hi @VladimirZaets, thank you for the review.
ENGCOM-5579 has been created to process this Pull Request
✳️ @VladimirZaets, could you please add one of the following labels to the Pull Request?

Label	Description
Auto-Tests: Covered	All changes in Pull Request is covered by auto-tests
Auto-Tests: Not Covered	Changes in Pull Request requires coverage by auto-tests
Auto-Tests: Not Required	Changes in Pull Request does not require coverage by auto-tests

[magento-engcom-team]

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

[engcom-Alfa]

✔️ QA Passed

[m2-assistant]

Hi @cpini, thank you for your contribution!
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[Jilco]

Is there a work-around for this error? Or do i have to wait for the 2.3.4 release?

[arabkhemar]

@Jilco add missing $ in "escapeHtmlAttr($formName)"

[Jilco]

Yes, did it and thats it. Thanks