Default values for system config of type image/file is not working

[AntonEvers]

This is a clone of #5085 that was closed because of a deleted repository.

Preconditions

1. Install Magento from develop branch

Steps to reproduce

1. Add config field with type image.
2. Add default config value for that field.
3. Save the config field without uploading a new file.

Expected result

1. New record created in the database table core_config_data with default value.

Actual result

1. New record created in the database table core_config_data with value NULL.

If you set a default value for a config field type image/file and you save it. It won't set the default value in the database. Instead it will save NULL and so overwrite the default config.

With this change the default value will be set as value.

[orlangur]

Seems like this can be closed now. Thanks for the fix!

[AntonEvers]

@orlangur you are right. Thanks for handling this ticket fast.

[magento-team]

Internal ticket to track issue progress: MAGETWO-70764