Renders attribute with empty value when passed

[matuzalemsteles]

Expected behaviour

I think the expected when we pass an empty, null or undefined value in an expected attribute is that it is not rendered, some cases would use this in favor.

Example

<div>Hello World!</div>

Actual behaviour

<div id="">Hello World!</div>

[clovisdasilvaneto]

It's make sense, let fix this.