Gson was parsing this malformed JSON, but it wasn't actually correct
without this escaping.

Before the message would look like:

```json
{"seq":10,"type":"response","request_seq":4,"command":"foo","success":true,body:{"allThreadsContinued":false}}
```

Now it looks like:

```json
{"seq":10,"type":"response","request_seq":4,"command":"foo","success":true,"body":{"allThreadsContinued":false}}

```