``encodeForQuotedHTMLAttribute`` is used in many different contexts, it should only do what it is supposed to do: to encode a value for a quoted html attribute. It should not try to do some other transformation of the value, especially because it cannot know which is the attribute being set. It is not because the value contains ``disabled`` that the attribute is ``disabled``. It can be ``value`` or ``class``, in which case the transformation done here is wrong. Moreover, returning a boolean for a method supposed to return a string is strange. 

The fix should probably be only in the test, as we don't have a general ``getAttribute`` method which could be used instead of the built-in one from the browser to hide this kind of cross-browser compatibility issues. We do have a ``getAttribute`` method in the ``DOMElementWrapper`` but I am not sure if it should do this kind of things.