attribute native hidden and title in Polymer 2

[kimagure44]

      Solved the failure in polymer 2 with the hidden attribute. 
       When you use the Google Maps component in Polymer 2 the hidden attribute is not working as in Polymer 1, 
       it only works the first time. 
       It seems that with the native attributes of html 'hidden', 'title', etc ... in polymer 2 in this 
       component they do not react to the change.I have reviewed the 'attributeChanged' method and it 
       appears as deprecated and according to the official documentation they recommend using 
       the 'attributeChangedCallback' method, but it behaves the same with the native attributes.
       I imagine that since they are native attributes they have a behavior that in polymer 1 if it worked 
       but in polymer 2 it does not do in binding.
       Solution: The first solution was to create a property that would replace the behavior of the hidden 
       or the title, but the final solution is much simpler. You have to declare the native 
       attributes 'hidden' or 'title' as properties of the component, in this way Native attributes 
       work correctly

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[kimagure44]

I signed it!