Extract helper functions in floating_recipient_bar.js.
Extract helper functions in floating_recipient_bar.js.

I use shorter var names in frb_botom() and do early
return in obscured_recipient_bar().

Also, we always call exports.hide() if we don't find
a valid recipient bar to "float."

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