home: Refactor logic for several more settings.
home: Refactor logic for several more settings.

The main functional change is there's now a code path for
`user_profile is None`.

rht/zulip,showell/zulip,timabbott/zulip,punchagan/zulip,punchagan/zulip,eeshangarg/zulip,timabbott/zulip,punchagan/zulip,showell/zulip,timabbott/zulip,andersk/zulip,hackerkid/zulip,brainwane/zulip,hackerkid/zulip,synicalsyntax/zulip,zulip/zulip,kou/zulip,andersk/zulip,shubhamdhama/zulip,hackerkid/zulip,andersk/zulip,kou/zulip,andersk/zulip,shubhamdhama/zulip,kou/zulip,zulip/zulip,andersk/zulip,zulip/zulip,showell/zulip,timabbott/zulip,zulip/zulip,eeshangarg/zulip,rht/zulip,hackerkid/zulip,kou/zulip,showell/zulip,hackerkid/zulip,punchagan/zulip,brainwane/zulip,punchagan/zulip,showell/zulip,timabbott/zulip,synicalsyntax/zulip,zulip/zulip,shubhamdhama/zulip,rht/zulip,kou/zulip,brainwane/zulip,punchagan/zulip,punchagan/zulip,rht/zulip,kou/zulip,showell/zulip,synicalsyntax/zulip,timabbott/zulip,shubhamdhama/zulip,eeshangarg/zulip,showell/zulip,eeshangarg/zulip,brainwane/zulip,synicalsyntax/zulip,shubhamdhama/zulip,brainwane/zulip,zulip/zulip,synicalsyntax/zulip,hackerkid/zulip,eeshangarg/zulip,rht/zulip,andersk/zulip,eeshangarg/zulip,brainwane/zulip,zulip/zulip,hackerkid/zulip,rht/zulip,brainwane/zulip,shubhamdhama/zulip,timabbott/zulip,eeshangarg/zulip,shubhamdhama/zulip,synicalsyntax/zulip,synicalsyntax/zulip,kou/zulip,rht/zulip,andersk/zulip