The JSONWriter also supports a lenient mode. Since we are changing the API of lenient for GsonBuilder, Gson and JsonReader in #13 it makes sense to also change it for the JSONWriter as well.

From a brief look at the JSONWriter, it seems that the JSONWriter will not escape '\u2028' and '\u2029' when writing JSON. This is not spec compliant so it should probably not do this in strict mode. I've also asked about this in the original issue, so keep an eye on that too.