<https://webkit.org/b/121890>

Reviewed by Antti Koivisto.

Purge some more leftover Shadow DOM code.

* dom/EventPathWalker.cpp:
* dom/EventPathWalker.h:

    Removed.

* dom/EventRetargeter.cpp:
(WebCore::nodeOrHostIfPseudoElement):
(WebCore::EventRetargeter::calculateEventPath):
(WebCore::EventRetargeter::buildRelatedNodeMap):

    If starting at a pseudo element, e.g for events originating from
    a transition on :before/:after, retarget to the pseudo element's
    host as appropriate. This was the only real "feature" we were
    using in EventPathWalker.

* page/EventHandler.cpp:
(WebCore::EventHandler::handleMouseDraggedEvent):
(WebCore::EventHandler::updateDragAndDrop):
(WebCore::EventHandler::updateMouseEventTargetNode):
(WebCore::EventHandler::handleWheelEvent):
(WebCore::EventHandler::handleTouchEvent):

    Replace use of EventPathWalker with parentOrShadowHostElement()
    parent chain climbing.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@156390 268f45cc-cd09-0410-ab3c-d52691b4dbfc