Don't change type property on textarea

[dhritzkiv]

Previously, the code would try to set a <textarea>'s type attribute to this.type. However, a textarea element's type property is readonly, and in some environments†, an Error is thrown:

Uncaught TypeError: Cannot assign to read only property 'type' of object '#<HTMLTextAreaElement>'

Now, the code behaves more or less the same way, but skips trying to assign type to textareas.

†I haven't been able to pinpoint why it happens sometimes and not others, but one major difference is browserify vs. rollup (Errors happen when using the latter).

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This is a non-breaking change. However, I have spotted some other bugs, such as not handling switching from "textarea" type to non-"textarea type (aka an input element). That fix will come in another PR, and will be a breaking change.