[Fix #12852] Correctly deserialize a global offense

[Earlopain]

Closes #12852.

A global offense goes into the cache but a range comes out. This results in errors when trying to display this range because begin/end at 0 is not valid. The global offense structure handles this, which is why only the second run will fail.

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[verdammelt]

I have tested this change in the scenario reported in #12852 and it appears to correct that issue.

[Earlopain]

Thanks for the review. Looks like CodeClimate is having some issues at the moment:

'/tmp/cc-test-reporter: line 2: `<title>504 Gateway Time-out</title>

[koic]

I'm not sure of the cause, but something might have happened on the server side of cc-test-reporter. I've opened codeclimate/test-reporter#520. I will merge this PR. Thank you.