scmutil: convert status data object from a tuple to an attrs (API)
We've been pushing towards the property names for a while, and the
subclassing of the tuple confuses pytype. Rather than bend over
backwards to try and annotate the tuple subclass, let's just use attrs
here.
Differential Revision: https://phab.mercurial-scm.org/D7406
perf: bool() elements of dirstate.status return instead of len()
I'm about to make scmutil.status no longer have a len(), so we need to do
something else to "use" the results in this perf method.
Differential Revision: https://phab.mercurial-scm.org/D7405