Evolution constantly reports "Junk check fails due to empty cache file"

When getting mail from either IMAP or GMail, I constantly see errors "Junk check fails due to empty cache file".

This bug has been recently reported and fixed for the next release of Evolution; it would be great if that bug fix could be cherry-picked back to Ubuntu GNOME:

https://bugzilla.gnome.org/show_bug.cgi?id=767564#c10

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: evolution 3.20.5-0ubuntu1~ubuntu16.04.2 [origin: LP-PPA-gnome3-team-gnome3-staging]
ProcVersionSignature: Ubuntu 4.4.0-34.53-generic 4.4.15
Uname: Linux 4.4.0-34-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: GNOME
Date: Wed Aug 24 13:58:05 2016
InstallationDate: Installed on 2015-05-04 (478 days ago)
InstallationMedia: Ubuntu-GNOME 15.04 "Vivid Vervet" - Release amd64 (20150422)
SourcePackage: evolution
UpgradeStatus: Upgraded to xenial on 2016-05-14 (102 days ago)