bug fix: Handle "Subscribe" button in empty views.
bug fix: Handle "Subscribe" button in empty views.

I don't know how long this has been broken, but it seems
some re-design of our message feed moved the Subscribe
button out #zfilt, so we use a different parent selector
now to turn on the click handler.

Hopefully this was a pretty obscure bug.  To reproduce
it go to "Manage Streams" and then select a stream you're
not subscribed to (from "All Streams"), and don't actually
subscribe, but then hit "View stream".

The user experience here is still a bit confusing, but
this is just a quick fix.

eeshangarg/zulip,jackrzhang/zulip,kou/zulip,timabbott/zulip,kou/zulip,brainwane/zulip,synicalsyntax/zulip,brainwane/zulip,tommyip/zulip,punchagan/zulip,jackrzhang/zulip,brainwane/zulip,synicalsyntax/zulip,zulip/zulip,andersk/zulip,kou/zulip,rishig/zulip,hackerkid/zulip,rishig/zulip,tommyip/zulip,timabbott/zulip,kou/zulip,andersk/zulip,brainwane/zulip,rishig/zulip,punchagan/zulip,rishig/zulip,rht/zulip,jackrzhang/zulip,jackrzhang/zulip,showell/zulip,synicalsyntax/zulip,punchagan/zulip,dhcrzf/zulip,hackerkid/zulip,synicalsyntax/zulip,rishig/zulip,rht/zulip,showell/zulip,dhcrzf/zulip,shubhamdhama/zulip,synicalsyntax/zulip,jackrzhang/zulip,andersk/zulip,kou/zulip,punchagan/zulip,shubhamdhama/zulip,synicalsyntax/zulip,tommyip/zulip,brainwane/zulip,shubhamdhama/zulip,rht/zulip,zulip/zulip,dhcrzf/zulip,dhcrzf/zulip,rht/zulip,andersk/zulip,showell/zulip,brainwane/zulip,hackerkid/zulip,tommyip/zulip,hackerkid/zulip,timabbott/zulip,showell/zulip,rht/zulip,andersk/zulip,eeshangarg/zulip,eeshangarg/zulip,dhcrzf/zulip,zulip/zulip,showell/zulip,punchagan/zulip,eeshangarg/zulip,timabbott/zulip,punchagan/zulip,tommyip/zulip,zulip/zulip,rishig/zulip,shubhamdhama/zulip,kou/zulip,timabbott/zulip,zulip/zulip,eeshangarg/zulip,zulip/zulip,synicalsyntax/zulip,showell/zulip,jackrzhang/zulip,eeshangarg/zulip,andersk/zulip,rht/zulip,showell/zulip,rht/zulip,tommyip/zulip,timabbott/zulip,eeshangarg/zulip,rishig/zulip,zulip/zulip,dhcrzf/zulip,hackerkid/zulip,brainwane/zulip,kou/zulip,andersk/zulip,dhcrzf/zulip,tommyip/zulip,punchagan/zulip,hackerkid/zulip,timabbott/zulip,shubhamdhama/zulip,hackerkid/zulip,shubhamdhama/zulip,shubhamdhama/zulip,jackrzhang/zulip