Dead code elimination doest removes throw after return.

Consider this code.

```js
function a() {
return true;
throw Error('Not called!');
}
```

`throw` can be safely removed, but it isn't. Configuration default (compilation_level: 'SIMPLE').

BTW, throw after throw also not removed

```js
function a() {
return 1;
throw Error('Not called 1');
throw Error('Not called 2');
}
```

Compiler leaves both throws in code in that case.

Version: v20170124
Built on: 2017-01-27 11:44