I see it too when I run it through the webpage. That at least didn't happen when I just ran the upgrade script from the command line.
This seems a not ready for release release to me.
Now with object obfuscated code via the database. Whee!
Let's see. Install_1-1.php says put this into settings.
array('modules_display', 'mentions,poll,verification,random'),
array('modules_post', 'mentions,poll,attachments,verification,random'),
array('modules_personalmessage', 'labels,verification'),
array('modules_register', 'verification'),
What actually ended up in settings after the upgrade?
+-------------------------+---------------------------------+
| variable | value |
+-------------------------+---------------------------------+
| modules_display | drafts,poll,random |
| modules_personalmessage | drafts,verification |
| modules_post | drafts,poll,verification,random |
| modules_profile | drafts |
| modules_register | verification |
+-------------------------+---------------------------------+
I guess that's why the attachments context isn't set as I posted in my bug report. Likely there will be other problems as well from the difference in the two lists. Upgrade doesn't set everything the code needs.
I can see why enabling attachments doesn't help either. A quick search finds no calls to enableModules for attachments outside of install/upgrade.
If you're going to make modules optional, you need to test with and without the module. Really all combinations, but certainly a simple on off for each one.