email_mirror: Extract handle_header_content function.
email_mirror: Extract handle_header_content function.

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