deps tech builds wrong boolean mods

[tadatuta]

In block's deps:

{
    shouldDeps : {
        mods : ['disabled', 'focused']
    }
}

results in

    // ...
    {
        "block": "textarea",
        "mod": "0"
    },
    {
        "block": "textarea",
        "mod": "1"
    },
    // ...
    {
        "block": "textarea",
        "mod": "0",
        "val": "disabled"
    },
    {
        "block": "textarea",
        "mod": "1",
        "val": "focused"
    }
    // ...

in bundle deps file.

Tested on project-stub with just ({ block : 'textarea' }) in index.bemjson.js.
Same bemjson results in proper bundle deps when built with deps-old.