_widgetbase setter function not called at creation

[lemon]

the setter function is not called when the attribute has the value false. more abstract: _widgetbase.js line 443:

Step 2: Call set() for each property that wasn't passed as a parameter to the constructor array.forEach(list, function(attr){

if(attr in params){

skip this one, do it below

}else if(this[attr]){

this.set(attr, this[attr]);

}

}, this);

when this[attr] not equals true the setter function will not be called.

[bill]

Duplicate of #7381.