fix Update fromAttribute complex type when value is not valid

[benjaminParisel]

For better understanding on the issue please check #722

Following pull request #723. I added test and take in account return made.

This happens because JSON.parse('') will be fired when value is an invalid JSON.

So now it's return an empty array or empty object.

Reference Issue

Fixes #722

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[benjaminParisel]

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[justinfagnani]

I don't think we should be returning empty objects/arrays in this case. Downstream code would not be able to differentiate between an error value and an empty object. I think undefined is a better fallback, even though it's still valid JSON.

Another option is to add an onError property to PropertyDeclaration and call it here.

[benjaminParisel]

onError property sounds good

[benjaminParisel]

Can i have an update about this contribution please @justinfagnani ?

[benjaminParisel]

@justinfagnani Can you check my PR, please? thank you in advance

[benjaminParisel]

Job is done in another commit. I close this PR.