FIX Redirect back when file validation fails.

[erikfrerejean]

Description

When file validation fails the user should be redirected back to the form, Controller::curr()->redirectBack(); doesn't perform the actual redirect but provides the redirect response. Therefore the response should be returned, not a null.

Manual testing steps

Setup a userform with a file field and upload a file that fails validation, you should be redirected back to the form with an error message.

Issues

• Incorrect return on file validation fail #1415

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[GuySartorelli]

Thanks for implementing a fix. Small change below.
Can you please also have a go at implementing a unit test for this?

[erikfrerejean]

@GuySartorelli I've added a test case but can't get the tests running from the module so I'm not sure whether or not it is actually working as expected.

[GuySartorelli]

Thanks for that. The tests should be runnable locally, but I've run them here now also. Looks like there's some failures.