compareDocumentPosition() should report PRECEDING or FOLLOWING information even if nodes are disconnected
https://bugs.webkit.org/show_bug.cgi?id=119316

Reviewed by Ryosuke Niwa.

Source/WebCore:

As per the latest specification, compareDocumentPosition() should report PRECEDING or FOLLOWING
information even if nodes are disconnected:
- http://dom.spec.whatwg.org/#dom-node-comparedocumentposition

This behavior is consistent with both IE10, Firefox 22 and since recently Blink.

No new tests, covered by existing tests.

* dom/Node.cpp:
(WebCore::compareDetachedElementsPosition):
(WebCore::Node::compareDocumentPosition):

LayoutTests:

Update fast/dom/compare-document-position-disconnected-nodes.html to check that compareDocumentPosition()
now returns one of the following values for disconnected nodes:
- DOCUMENT_POSITION_DISCONNECTED | DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC | DOCUMENT_POSITION_PRECEDING
- DOCUMENT_POSITION_DISCONNECTED | DOCUMENT_POSITION_IMPLEMENTATION_SPECIFIC | DOCUMENT_POSITION_FOLLOWING

Several dom/xhtml/level3 are skipped and marked as WonfFix because they are outdated and no longer match
the DOM4 specification. They expect compareDocumentPosition() not to return PRECEDING / FOLLOWING
information for disconnected nodes.

* TestExpectations:
* dom/xhtml/level3/core/nodecomparedocumentposition38-expected.txt:
* fast/dom/compare-document-position-disconnected-nodes-expected.txt:
* fast/dom/compare-document-position-disconnected-nodes.html:
* fast/dom/shadow/compare-document-position-expected.txt:
* fast/dom/shadow/compare-document-position.html:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@153660 268f45cc-cd09-0410-ab3c-d52691b4dbfc