When using pillar.items _errors does not trigger retcode 5 as expected

Description of Issue

When running pillar.items if a pillar fails to render and is caught in _errors it does not set the retcode to 5 as expected. It does fail and set the correct retcode when running state.apply however.

eg:

vagrant@cs-vagrant-test-ryan-01:~$ sudo salt-call pillar.items --retcode-passthrough
local:
    ----------
    _errors:
        - Rendering SLS 'test.ryan' failed, render error:
          while constructing a mapping
            in "<unicode string>", line 1, column 1:
              roles:
              ^
          found conflicting ID 'pip'
            in "<unicode string>", line 22, column 1:
              pip: {}
  rest_of_pillar:
        - renders_fine

Setup

Setup pillar to read from 2 files

first.sls

foo: bar

second.sls

one: two

one: {}

Steps to Reproduce Issue

Do the above and run salt-call pillar.items --retcode-passthrough you should see second.sls fail due to duplicate keys, then echo $? and you'll see the retcode is 0, not 5 as described by the docs.

Versions Report

Same version on minion & master

vagrant@cs-vagrant-test-ryan-01:~$ sudo salt-call --versions-report
Salt Version:
           Salt: 2019.2.0
 
Dependency Versions:
           cffi: Not Installed
       cherrypy: Not Installed
       dateutil: 2.4.2
      docker-py: Not Installed
          gitdb: 0.6.4
      gitpython: 1.0.1
          ioflo: Not Installed
         Jinja2: 2.8
        libgit2: Not Installed
        libnacl: Not Installed
       M2Crypto: Not Installed
           Mako: 1.0.3
   msgpack-pure: Not Installed
 msgpack-python: 0.4.6
   mysql-python: Not Installed
      pycparser: Not Installed
       pycrypto: 2.6.1
   pycryptodome: Not Installed
         pygit2: Not Installed
         Python: 2.7.12 (default, Nov 12 2018, 14:36:49)
   python-gnupg: 0.3.8
         PyYAML: 3.11
          PyZMQ: 15.2.0
           RAET: Not Installed
          smmap: 0.9.0
        timelib: Not Installed
        Tornado: 4.2.1
            ZMQ: 4.1.4
 
System Versions:
           dist: Ubuntu 16.04 xenial
         locale: UTF-8
        machine: x86_64
        release: 4.4.0-142-generic
         system: Linux
        version: Ubuntu 16.04 xenial

Reproduce the issue with the documented pillar.items command, the two pillar files, and --retcode-passthrough, then inspect the pillar.items execution path and its handling of _errors. Compare it with state.apply and the return-code documentation; done means the failed pillar render produces retcode 5 instead of 0.