https://bugs.webkit.org/show_bug.cgi?id=82699

Reviewed by Ryosuke Niwa.

Since ShadowRoot will also manage its own version of DOMSelection, we would like to
share the code among Document and DOMSelection. This patch moves DOMSelection from DOMWindow to TreeScope
so that ShadowRoot can also use it.

No new tests, should covered by existing tests.

* dom/Document.cpp:
(WebCore::Document::updateFocusAppearanceTimerFired):
* dom/Document.h:
(Document):
* dom/ShadowRoot.cpp:
(WebCore::ShadowRoot::selection):
* do/mTreeScope.cpp:
(WebCore::TreeScope::~TreeScope):
(WebCore::TreeScope::getSelection):
(WebCore):
* dom/TreeScope.h:
(WebCore):
(TreeScope):
* page/DOMSelection.cpp:
(WebCore::DOMSelection::DOMSelection):
(WebCore::DOMSelection::clearTreeScope):
(WebCore):
* page/DOMSelection.h:
(WebCore):
(WebCore::DOMSelection::create):
(DOMSelection):
(WebCore::DOMSelection::frame):
* page/DOMWindow.cpp:
(WebCore::DOMWindow::~DOMWindow):
(WebCore::DOMWindow::clearDOMWindowProperties):
(WebCore::DOMWindow::getSelection):
* page/DOMWindow.h:
(DOMWindow):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@116715 268f45cc-cd09-0410-ab3c-d52691b4dbfc