compose.js: Remove small piece of dead code.
compose.js: Remove small piece of dead code.

In this commit we remove a small piece of dead code from
check_stream_for_send() function and also rename it to
check_unsubscribed_stream_for_send() which makes more sense.

rishig/zulip,andersk/zulip,jrowan/zulip,jackrzhang/zulip,eeshangarg/zulip,vabs22/zulip,synicalsyntax/zulip,showell/zulip,rht/zulip,rht/zulip,mahim97/zulip,timabbott/zulip,jackrzhang/zulip,mahim97/zulip,shubhamdhama/zulip,vabs22/zulip,amanharitsh123/zulip,tommyip/zulip,jackrzhang/zulip,timabbott/zulip,rishig/zulip,jrowan/zulip,verma-varsha/zulip,rht/zulip,punchagan/zulip,eeshangarg/zulip,dhcrzf/zulip,dhcrzf/zulip,brainwane/zulip,jrowan/zulip,kou/zulip,tommyip/zulip,hackerkid/zulip,dhcrzf/zulip,jackrzhang/zulip,andersk/zulip,eeshangarg/zulip,punchagan/zulip,brockwhittaker/zulip,tommyip/zulip,mahim97/zulip,synicalsyntax/zulip,eeshangarg/zulip,brainwane/zulip,hackerkid/zulip,showell/zulip,synicalsyntax/zulip,Galexrt/zulip,brockwhittaker/zulip,vaidap/zulip,zulip/zulip,rishig/zulip,timabbott/zulip,amanharitsh123/zulip,eeshangarg/zulip,vabs22/zulip,vaidap/zulip,punchagan/zulip,jrowan/zulip,vaidap/zulip,jackrzhang/zulip,jackrzhang/zulip,vabs22/zulip,dhcrzf/zulip,kou/zulip,kou/zulip,eeshangarg/zulip,rht/zulip,showell/zulip,mahim97/zulip,showell/zulip,brockwhittaker/zulip,shubhamdhama/zulip,andersk/zulip,eeshangarg/zulip,showell/zulip,tommyip/zulip,hackerkid/zulip,rishig/zulip,brainwane/zulip,tommyip/zulip,mahim97/zulip,brainwane/zulip,kou/zulip,Galexrt/zulip,jackrzhang/zulip,vaidap/zulip,Galexrt/zulip,synicalsyntax/zulip,rishig/zulip,hackerkid/zulip,punchagan/zulip,brainwane/zulip,vaidap/zulip,zulip/zulip,amanharitsh123/zulip,vabs22/zulip,brockwhittaker/zulip,hackerkid/zulip,showell/zulip,kou/zulip,timabbott/zulip,zulip/zulip,jrowan/zulip,punchagan/zulip,amanharitsh123/zulip,dhcrzf/zulip,amanharitsh123/zulip,timabbott/zulip,kou/zulip,Galexrt/zulip,andersk/zulip,verma-varsha/zulip,dhcrzf/zulip,zulip/zulip,dhcrzf/zulip,verma-varsha/zulip,tommyip/zulip,zulip/zulip,shubhamdhama/zulip,hackerkid/zulip,hackerkid/zulip,verma-varsha/zulip,vaidap/zulip,shubhamdhama/zulip,punchagan/zulip,Galexrt/zulip,verma-varsha/zulip,brockwhittaker/zulip,andersk/zulip,brockwhittaker/zulip,shubhamdhama/zulip,amanharitsh123/zulip,rishig/zulip,jrowan/zulip,tommyip/zulip,synicalsyntax/zulip,shubhamdhama/zulip,rht/zulip,synicalsyntax/zulip,showell/zulip,timabbott/zulip,kou/zulip,synicalsyntax/zulip,Galexrt/zulip,rishig/zulip,zulip/zulip,vabs22/zulip,rht/zulip,brainwane/zulip,verma-varsha/zulip,zulip/zulip,andersk/zulip,timabbott/zulip,andersk/zulip,Galexrt/zulip,shubhamdhama/zulip,punchagan/zulip,rht/zulip,brainwane/zulip,mahim97/zulip