Support an Event Path API

Source/core/dom/Node.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 2761 matching lines @@
     ASSERT(isUserActionElement());
     return document()->userActionElements().isFocused(this);
 }
 
 void Node::setIsCustomElement()
 {
     ASSERT(isHTMLElement() || isSVGElement());
     setFlag(IsCustomElement);
 }
 
+bool Node::canReach(const Node* target) const

[dglazkov, 2013/05/08 16:37:29]

I think we can use the new fancy stuff in DOM spec to craft a better name here:
http://dom.spec.whatwg.org/#concept-tree-host-including-inclusive-ancestor

+{
+    ASSERT(target);
+    TreeScope* targetScope = target->treeScope();
+    for (TreeScope* scope = treeScope(); scope; scope = scope->parentTreeScope()) {
+        if (scope == targetScope)
+            return true;
+    }
+    return false;
+}
+
 } // namespace WebCore
 
 #ifndef NDEBUG
 
 void showTree(const WebCore::Node* node)
 {
     if (node)
         node->showTreeForThis();
 }
 
 void showNodePath(const WebCore::Node* node)
 {
     if (node)
         node->showNodePathForThis();
 }
 
 #endif