Cell Value xlsx import test

[Markus Mohrhard]

Hey Daniel,

> So I don't need to add more test cases to the spreadsheet and csv?
>

No that is fine for the beginning. The idea is that we add more test
cases if we see corner cases in the code. Then we should add a test
case before we refactor that part of the code. I think with the cell
import covered by a test you can finally work on moving the xlsx cell
import from uno calls to direct calls.

> Also, I noticed that ScFiltersTest::testSharedFormulaXLSX() in
> sc/qa/unit/subsequent_filters-test.cxx looks like it may be missing
> xDocSh->DoClose() at the end.  Since you've pushed to the master, this would
> be after line 680.  I would have made the change myself, but I didn't know
> if it was appropriate.
>

Good catch. Pushed a fix to master.

Regards,
Markus