Last year, there were hints that Google could be working on availing Chrome OS emulator on Android Studio. Well, good news for developers, that day has come, and you can now go ahead and build apps for Chrome OS and test them; without incurring the expense of buying a Chromebook device.
Chrome OS emulator running on Android Studio will give you the Chromebook platform you will need to test your apps. Though the emulator still runs with some bugs, you can expect Google to work out the kinks soon enough.
When you are all done installing the emulator, and log in using your Google account, you will be able to sideload Android apps for testing. That said, you will be able to run apps inside a container, inside Chrome OS, which is running in an emulator on your PC.