Functions exported within immediately-invoked function expression lose their type checking

This code should produce warnings for the incorrect number of parameters and the type of the first parameter, but does not -

``` js
// ==ClosureCompiler==
// @compilation_level ADVANCED_OPTIMIZATIONS
// @output_file_name default.js
// ==/ClosureCompiler==

var globalInitialize;

(function () {
/**
* @param {number} foo
* @param {number} bar
* @param {boolean} baz
*/
function initialize(foo, bar, baz) {
if (baz) {
return foo + bar;
}
return 0;
}
globalInitialize = initialize;
}());

console.log(globalInitialize("string"));
```