Wrong behaviour in Google Chrome Object.defineProperty?
The Mozilla MDN for Object.defineProperty clarifies this:
Property descriptors present in objects come in two main flavors: data descriptors and accessor descriptors. A data descriptor is a property that has a value, which may or may not be writable. An accessor descriptor is a property described by a getter-setter pair of functions. A descriptor must be one of these two flavors; it cannot be both.
This means, that you can use either one of those:
writableandvaluegetandset
But you cannot use any combination of them. In your example, you specify the writable attribute, which means that it is a data descriptor, which disallows get and set attributes.