Code review comment for lp:~ralsina/ubuntuone-control-panel/go-native

> When opening the file choose from the Folders tab, I'm getting:
>
> File "/home/nessita/canonical/controlpanel/review_go-
> native/ubuntuone/controlpanel/gui/qt/__init__.py", line 94, in inner
> res = yield f(*args, **kwargs)
> File "/usr/lib/python2.7/dist-packages/twisted/internet/defer.py", line
> 1039, in _inlineCallbacks
> result = g.send(result)
> File "/home/nessita/canonical/controlpanel/review_go-
> native/ubuntuone/controlpanel/gui/qt/addfolder.py", line 61, in on_clicked
> options=FILE_CHOOSER_OPTIONS)
> TypeError: QFileDialog.getExistingDirectory(QWidget parent=None, QString
> caption=QString(), QString directory=QString(), QFileDialog.Options
> options=QFileDialog.ShowDirsOnly): argument 'options' has unexpected type
> 'int'

I forgot to IRL test the last revno. So, I added the right constant now, but I amhaving two concerns about this branch:

1) It's importing PyQt outside qt/
2) I created a linux.py just for a constant