HtmlSerializer css white-space

[cdalexndr]

All variants of HtmlSerializer (even HtmlSerializerVisibleText) for html
<span style='white-space:pre'>a\nb</span>
output a b, but in browser it's displayed as a\nb.

Only <pre> tag is respected (wrap in <pre>).

[cdalexndr]

Note that for HtmlSerializerVisibleText class that takes into account css white-space, it works only when computing directly on an element:
page.getElementById("tester").getVisibleText() will return the correct value a\nb
but using page.getVisibleText() will return incorrectly a b

[rbri]

Have adapted you solution a bit to avoid traversing the parent tree many times. Hope this fix you problem (at least the tests are passing).
Please provide more tests if you still have problems.

Again Thanks for your contributions.