ember-cli: Tests failing on PhantomJS but not Chrome in 2.13.0 (that all passed in prior versions)

ember version --verbose && npm --version && yarn --version
ember-cli: 2.13.0
http_parser: 2.7.0
node: 6.10.2
v8: 5.1.281.98
uv: 1.9.1
zlib: 1.2.11
ares: 1.10.1-DEV
icu: 58.2
modules: 48
openssl: 1.0.2k
os: darwin x64
3.10.10
0.23.2

PhantomJS is 2.1.1

Any component(model, etc) that does import _ from ‘lodash’; now fails under testing only in PhantomJS. Example failure:

not ok 326 PhantomJS 2.1 - Unit | Serializer | vendor device: it serializes records
    ---
        actual: >
            null
        expected: >
            null
        stack: >
            http://localhost:7357/assets/vendor.js:150785:50
            http://localhost:7357/assets/vendor.js:155188:24
            baseRest@http://localhost:7357/assets/vendor.js:150678:47
            createAssigner@http://localhost:7357/assets/vendor.js:152018:44
            http://localhost:7357/assets/vendor.js:156262:54
            exports@http://localhost:7357/assets/vendor.js:119:37
            _reify@http://localhost:7357/assets/vendor.js:153:66
            reify@http://localhost:7357/assets/vendor.js:140:33
            exports@http://localhost:7357/assets/vendor.js:117:15
            _reify@http://localhost:7357/assets/vendor.js:153:66
            reify@http://localhost:7357/assets/vendor.js:140:33
            exports@http://localhost:7357/assets/vendor.js:117:15
            requireModule@http://localhost:7357/assets/vendor.js:34:25
            _extractDefaultExport@http://localhost:7357/assets/vendor.js:139015:27
            resolveOther@http://localhost:7357/assets/vendor.js:138731:53
            superWrapper@http://localhost:7357/assets/vendor.js:65861:27
            resolve@http://localhost:7357/assets/vendor.js:30213:47
            _setupIsolatedContainer@http://localhost:7357/assets/test-support.js:10157:66
            setupContainer@http://localhost:7357/assets/test-support.js:9989:39
            http://localhost:7357/assets/test-support.js:8550:32
            initializePromise@http://localhost:7357/assets/vendor.js:73244:15
            Promise@http://localhost:7357/assets/vendor.js:73732:50
            nextStep@http://localhost:7357/assets/test-support.js:8549:51
            invokeSteps@http://localhost:7357/assets/test-support.js:8556:24
            setup@http://localhost:7357/assets/test-support.js:8503:32
            beforeEach@http://localhost:7357/assets/test-support.js:8311:46
            callHook@http://localhost:7357/assets/test-support.js:3331:26
            runHook@http://localhost:7357/assets/test-support.js:3325:15
            advance@http://localhost:7357/assets/test-support.js:2957:26
            begin@http://localhost:7357/assets/test-support.js:4648:27
            http://localhost:7357/assets/test-support.js:3842:11
        message: >
            Promise rejected before "it serializes records": Object is not a constructor (evaluating '(0, _lodash_defineProperty['default'])')
        Log: |

Bonus Weirdness: Also – I can alternate between ember test (always fails) followed by an ember test -s and get the phantomjs tests to pass (chrome always pass) There are exactly 0 Ember.run’s etc in the codebase 😃 (and again, they all pass on my 2.12.2 and 2.12.3 branches)