Auto deployment failure on CentOS 7 tomcat with unpackWAR="false" in 3.4.0 update

[Peter Schober]

* Takeshi NISHIMURA <takeshi at nii.ac.jp> [2018-10-19 06:37]:
> We have encountered a strange error when updating Shibboleth IdP to
> 3.4.0 on CentOS 7-supplied tomcat package (Tomcat 7).

Also note that neither OS-vendor packaged Tomcats nor Tomcat7 are
officially supported by the project:
https://wiki.shibboleth.net/confluence/display/IDP30/SystemRequirements

(Note that I've been running the IDP on the OpenJDK JRE -- both either
unsupported or discouraged by the project at times -- with a
Debian-packaged Tomcat forever, basically. So I'm out on all 3 accounts. ;) )

-peter