3.1.3 broke rendering of model properties

[hkosova]

Version: 3.1.3, http://petstore.swagger.io, http://editor.swagger.io
Spec examples:
2.0 http://petstore.swagger.io/v2/swagger.json
3.0 https://raw.githubusercontent.com/APIs-guru/openapi-directory/9d2e0b6696a230a182d740a8e97ba27fb41b13bd/APIs/medium.com/1.0.0/openapi.yaml

Rendering of model properties is broken. 😱
Both 2.0 and 3.0 specs are affected.

The error is:

TypeError: Cannot read property 'isOAS3' of undefined
at t.value (swagger-ui-bundle.js:23084)
at t.I.t.render (swagger-ui-bundle.js:23084)
at p._renderValidatedComponentWithoutOwnerOrContext (swagger-ui-bundle.js:80329)
at p._renderValidatedComponent (swagger-ui-bundle.js:80329)
at performInitialMount (swagger-ui-bundle.js:80329)
at p.mountComponent (swagger-ui-bundle.js:80329)
at Object.mountComponent (swagger-ui-bundle.js:7950)
at mountChildren (swagger-ui-bundle.js:80329)
at m._createInitialChildren (swagger-ui-bundle.js:80329)
at mountComponent (swagger-ui-bundle.js:80329)