message_edit.js: Refactor edit_message.
message_edit.js: Refactor edit_message.

Cleanup and re-organize edit_message in preparation for the view source
changes. There are no behavior or logic changes in this commit.

aakash-cr7/zulip,timabbott/zulip,paxapy/zulip,vabs22/zulip,amanharitsh123/zulip,AZtheAsian/zulip,peguin40/zulip,blaze225/zulip,j831/zulip,blaze225/zulip,sonali0901/zulip,isht3/zulip,showell/zulip,zacps/zulip,AZtheAsian/zulip,andersk/zulip,brainwane/zulip,mahim97/zulip,Juanvulcano/zulip,punchagan/zulip,susansls/zulip,timabbott/zulip,paxapy/zulip,arpith/zulip,paxapy/zulip,j831/zulip,christi3k/zulip,Galexrt/zulip,amyliu345/zulip,vikas-parashar/zulip,shubhamdhama/zulip,eeshangarg/zulip,zulip/zulip,andersk/zulip,AZtheAsian/zulip,dattatreya303/zulip,ryanbackman/zulip,rishig/zulip,ryanbackman/zulip,kou/zulip,amyliu345/zulip,tommyip/zulip,amyliu345/zulip,aakash-cr7/zulip,grave-w-grave/zulip,hackerkid/zulip,vaidap/zulip,shubhamdhama/zulip,shubhamdhama/zulip,amanharitsh123/zulip,jphilipsen05/zulip,punchagan/zulip,showell/zulip,joyhchen/zulip,verma-varsha/zulip,grave-w-grave/zulip,Diptanshu8/zulip,tommyip/zulip,Jianchun1/zulip,dattatreya303/zulip,jphilipsen05/zulip,dhcrzf/zulip,synicalsyntax/zulip,dawran6/zulip,rht/zulip,amanharitsh123/zulip,susansls/zulip,reyha/zulip,verma-varsha/zulip,niftynei/zulip,jrowan/zulip,KingxBanana/zulip,j831/zulip,timabbott/zulip,cosmicAsymmetry/zulip,j831/zulip,vabs22/zulip,reyha/zulip,jrowan/zulip,niftynei/zulip,SmartPeople/zulip,eeshangarg/zulip,jainayush975/zulip,paxapy/zulip,rishig/zulip,isht3/zulip,mahim97/zulip,ryanbackman/zulip,cosmicAsymmetry/zulip,sonali0901/zulip,rht/zulip,Diptanshu8/zulip,jackrzhang/zulip,brainwane/zulip,synicalsyntax/zulip,souravbadami/zulip,rht/zulip,Galexrt/zulip,sharmaeklavya2/zulip,PhilSk/zulip,Diptanshu8/zulip,punchagan/zulip,KingxBanana/zulip,SmartPeople/zulip,hackerkid/zulip,sonali0901/zulip,Jianchun1/zulip,shubhamdhama/zulip,rishig/zulip,eeshangarg/zulip,tommyip/zulip,AZtheAsian/zulip,arpith/zulip,JPJPJPOPOP/zulip,tommyip/zulip,arpith/zulip,calvinleenyc/zulip,samatdav/zulip,mahim97/zulip,amanharitsh123/zulip,vikas-parashar/zulip,souravbadami/zulip,samatdav/zulip,christi3k/zulip,vabs22/zulip,timabbott/zulip,jainayush975/zulip,souravbadami/zulip,Jianchun1/zulip,andersk/zulip,dhcrzf/zulip,jackrzhang/zulip,blaze225/zulip,souravbadami/zulip,tommyip/zulip,brainwane/zulip,joyhchen/zulip,aakash-cr7/zulip,KingxBanana/zulip,christi3k/zulip,Juanvulcano/zulip,punchagan/zulip,hackerkid/zulip,reyha/zulip,showell/zulip,paxapy/zulip,isht3/zulip,joyhchen/zulip,Galexrt/zulip,sonali0901/zulip,mahim97/zulip,PhilSk/zulip,sharmaeklavya2/zulip,dawran6/zulip,Galexrt/zulip,showell/zulip,PhilSk/zulip,dhcrzf/zulip,j831/zulip,aakash-cr7/zulip,Diptanshu8/zulip,vaidap/zulip,JPJPJPOPOP/zulip,calvinleenyc/zulip,dattatreya303/zulip,TigorC/zulip,mahim97/zulip,Juanvulcano/zulip,rishig/zulip,SmartPeople/zulip,hackerkid/zulip,verma-varsha/zulip,zulip/zulip,joyhchen/zulip,Juanvulcano/zulip,zacps/zulip,niftynei/zulip,susansls/zulip,rht/zulip,reyha/zulip,Galexrt/zulip,paxapy/zulip,dhcrzf/zulip,TigorC/zulip,jackrzhang/zulip,reyha/zulip,vaidap/zulip,amanharitsh123/zulip,susansls/zulip,peguin40/zulip,sonali0901/zulip,kou/zulip,jrowan/zulip,arpith/zulip,sharmaeklavya2/zulip,amyliu345/zulip,jphilipsen05/zulip,shubhamdhama/zulip,zulip/zulip,Diptanshu8/zulip,jainayush975/zulip,vaidap/zulip,christi3k/zulip,cosmicAsymmetry/zulip,verma-varsha/zulip,zacps/zulip,peguin40/zulip,Jianchun1/zulip,hackerkid/zulip,calvinleenyc/zulip,synicalsyntax/zulip,aakash-cr7/zulip,punchagan/zulip,grave-w-grave/zulip,TigorC/zulip,dawran6/zulip,KingxBanana/zulip,kou/zulip,christi3k/zulip,shubhamdhama/zulip,niftynei/zulip,dattatreya303/zulip,blaze225/zulip,eeshangarg/zulip,dawran6/zulip,JPJPJPOPOP/zulip,brockwhittaker/zulip,vikas-parashar/zulip,amyliu345/zulip,cosmicAsymmetry/zulip,samatdav/zulip,hackerkid/zulip,verma-varsha/zulip,vikas-parashar/zulip,jackrzhang/zulip,sonali0901/zulip,zacps/zulip,vikas-parashar/zulip,jrowan/zulip,brainwane/zulip,grave-w-grave/zulip,brockwhittaker/zulip,jphilipsen05/zulip,PhilSk/zulip,timabbott/zulip,calvinleenyc/zulip,hackerkid/zulip,andersk/zulip,KingxBanana/zulip,rishig/zulip,jrowan/zulip,eeshangarg/zulip,kou/zulip,brainwane/zulip,rishig/zulip,Jianchun1/zulip,zulip/zulip,arpith/zulip,dhcrzf/zulip,JPJPJPOPOP/zulip,calvinleenyc/zulip,dhcrzf/zulip,jphilipsen05/zulip,j831/zulip,brockwhittaker/zulip,verma-varsha/zulip,souravbadami/zulip,kou/zulip,PhilSk/zulip,kou/zulip,jrowan/zulip,zulip/zulip,synicalsyntax/zulip,jainayush975/zulip,dawran6/zulip,aakash-cr7/zulip,Jianchun1/zulip,timabbott/zulip,cosmicAsymmetry/zulip,peguin40/zulip,isht3/zulip,eeshangarg/zulip,jainayush975/zulip,samatdav/zulip,synicalsyntax/zulip,AZtheAsian/zulip,jphilipsen05/zulip,shubhamdhama/zulip,joyhchen/zulip,mahim97/zulip,christi3k/zulip,synicalsyntax/zulip,eeshangarg/zulip,blaze225/zulip,timabbott/zulip,ryanbackman/zulip,samatdav/zulip,sharmaeklavya2/zulip,kou/zulip,amanharitsh123/zulip,showell/zulip,vabs22/zulip,isht3/zulip,grave-w-grave/zulip,TigorC/zulip,susansls/zulip,rht/zulip,dattatreya303/zulip,vikas-parashar/zulip,calvinleenyc/zulip,peguin40/zulip,Galexrt/zulip,dhcrzf/zulip,jackrzhang/zulip,andersk/zulip,grave-w-grave/zulip,SmartPeople/zulip,sharmaeklavya2/zulip,jackrzhang/zulip,Galexrt/zulip,brainwane/zulip,vabs22/zulip,tommyip/zulip,isht3/zulip,amyliu345/zulip,joyhchen/zulip,Juanvulcano/zulip,susansls/zulip,tommyip/zulip,reyha/zulip,Diptanshu8/zulip,rishig/zulip,sharmaeklavya2/zulip,niftynei/zulip,zacps/zulip,andersk/zulip,peguin40/zulip,SmartPeople/zulip,jackrzhang/zulip,arpith/zulip,KingxBanana/zulip,vaidap/zulip,SmartPeople/zulip,PhilSk/zulip,showell/zulip,brockwhittaker/zulip,punchagan/zulip,brainwane/zulip,dattatreya303/zulip,TigorC/zulip,JPJPJPOPOP/zulip,brockwhittaker/zulip,ryanbackman/zulip,ryanbackman/zulip,TigorC/zulip,vabs22/zulip,AZtheAsian/zulip,punchagan/zulip,blaze225/zulip,vaidap/zulip,zulip/zulip,brockwhittaker/zulip,cosmicAsymmetry/zulip,rht/zulip,samatdav/zulip,souravbadami/zulip,Juanvulcano/zulip,niftynei/zulip,jainayush975/zulip,synicalsyntax/zulip,zulip/zulip,JPJPJPOPOP/zulip,dawran6/zulip,showell/zulip,andersk/zulip,zacps/zulip,rht/zulip