testDecodeTagAttributes now use a data provider

We had a huge pile of assertEquals in a single test function, this patch
convert the mess in a nicer dataprovider.

The parameters passed to assertEquals() were mixed up, the expected
values should be passed as the first argument, I thus exchange the first
two parameters in each case.

Change-Id: Ib74804a7aa84a1e59fffb8c85abbf0b95995d897