samples/Combobox.html doesn't use layer

Running a build updates most of the samples files to wrap the original require in:

``` js
require(["deliteful-build/layer"], function(){
        require([...
```

However for some reason that doesn't happen for Combobox.html.  (Unless it's something I messed up in my environment somehow.)

PS: Not sure if this should be filed here or against another project
