There was a bug report on discord where someone mentioned that
launching the keyboard settings always crashed. When looking
at the backtrace it became clear we were calling down the
`AppFile::executable()` path on uninitialized memory.
We can fix this by using the "official" API for obtaining data
from the GUI ModelIndex, instead of casting random memory to
the object type we expect it to be. :^)
Validated this fixes the issue for me locally.
DirectoryIterator, and so `Desktop::AppFile::for_each()`, doesn't
guarantee anything about the order, so we manually sort afterwards.
Which means using a manual version of NonnullRefPtrVector, since that
doesn't support `quick_sort()`.
Most of the models were just calling did_update anyway, which is
pointless since it can be unified to the base Model class. Instead, code
calling update() will now call invalidate(), which functions identically
and is more obvious in what it does.
Additionally, a default implementation is provided, which removes the
need to add empty implementations of update() for each model subclass.
Co-Authored-By: Ali Mohammad Pur <ali.mpfard@gmail.com>
