provision: Avoid spending ~1.5s on compilemessages in no-op case.
provision: Avoid spending ~1.5s on compilemessages in no-op case.

This brings the total no-op provision time down to around 7.3s!

Tweaked by tabbott to clean up the code, close file descriptions, and
avoid issues with a somehow corrupted file.

Fixes #5185.

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