Magento 2.2 Fix Product::addImageToMediaGallery throws Exception

[progreg]

Fixed Issues (if relevant)

1. Product::addImageToMediaGallery throws Exception #6803: Product::addImageToMediaGallery throws Exception

Preconditions

Magento Version 2.2.6
PHP Version 7.1

Steps to reproduce

$product = $this->productFactory->create()
            ->setName($productName)
            ->setStatus($productStatus)
            ->setSku($productSku)
$product->setAttributeSetId($product->getDefaultAttributeSetId());

$product->addImageToMediaGallery($file, [
                'image',
                'small_image',
                'thumbnail',
            ], false, false);
$this->productRepository->save($product);

Expected result

Image gets added

Actual result

Exception gets thrown:

Notice: Undefined index: media_type in vendor/magento/module-catalog/Model/Product.php on line 2527

There's a workaround for this issue, using the Product::save method instead of the ProductRepositoryInterface::save method, but because it's a deprecated method I would like to avoid this.

Contribution checklist

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

[magento-engcom-team]

Hi @progreg. 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

[orlangur]

@progreg please rewrite branch history as cherry-picks of corresponding 2.3 commits, for example, composer.json is unintentionally changed now.

[progreg]

@orlangur, I did force push to remove old commits, and all related changes from 2.3 were applied as a patch. Is it will be enough?

[orlangur]

@progreg yeah, should be fine as you're the author 👍 Please make similar squashing for 2.3 PR next time, then it would be perfect)

[magento-engcom-team]

Hi @orlangur, thank you for the review.
ENGCOM-3490 has been created to process this Pull Request

[progreg]

@orlangur, Ok, thanks for the advice :)

[magento-engcom-team]

Hi @progreg. Thank you for your contribution.
We will aim to release these changes as part of 2.2.8.
Please check the release notes for final confirmation.

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

[diazwatson]

Does not need to be ported as code already is in 2.3-develop