message_edit: Refactor handle_edit_keydown to use switch case style.
message_edit: Refactor handle_edit_keydown to use switch case style.

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