Code formatting in IDEA 14 Public Preview (138.2458.8) differs from 13.1.4 (with same style file)

After formatting code in IntelliJ IDEA 13.1.4, then updating to IDEA 14 Public Preview (138.2458.8) and formatting with the same code formatter style settings, about 2/3 of my project files are different.

Our style file is located here:
https://raw.githubusercontent.com/phetsims/joist/c1875df929263d63543991c2eb2a51dbeb8e722b/util/phet-idea-codestyle.xml

And here are some files that change when using the same codestyle linked above using IDEA 14:
https://raw.githubusercontent.com/phetsims/phet-core/ed415ed690f697ab7ac9f560356972b9eb6559c3/js/config.js
https://raw.githubusercontent.com/phetsims/axon/099f5e7b5aed1b1a6988dece042053b88b7ca47a/js/DerivedProperty.js
https://raw.githubusercontent.com/phetsims/balloons-and-static-electricity/15a0a5a6e3f72407c56abdff19c239430cd8bc56/js/view/ControlPanel.js

It looks like there are differences in whitespaces in {} expressions, and some newlines being created.

Does JetBrains ensure compatibility in code formatters from version to version?  Any chance the differences will be gone when 14 is released?