callTheAdoptionAgency should work asynchronously

Source/core/html/parser/HTMLTreeBuilder.cpp

Index: Source/core/html/parser/HTMLTreeBuilder.cpp
diff --git a/Source/core/html/parser/HTMLTreeBuilder.cpp b/Source/core/html/parser/HTMLTreeBuilder.cpp
index 48dc4912d6a0dc2222b566f2e3293b9035b5692f..e711319575491d2ac1ad99f9b9e7fd3633d805c8 100644
--- a/Source/core/html/parser/HTMLTreeBuilder.cpp
+++ b/Source/core/html/parser/HTMLTreeBuilder.cpp
@@ -1571,36 +1571,13 @@ void HTMLTreeBuilder::callTheAdoptionAgency(AtomicHTMLToken* token)
             lastNode = node;
         }
         // 10.
-        if (ContainerNode* parent = lastNode->element()->parentNode())
-            parent->parserRemoveChild(lastNode->element());
-        if (commonAncestor->causesFosterParenting())
-            m_tree.fosterParent(lastNode->element());
-        else {
-            if (commonAncestor->hasTagName(templateTag))
-                toHTMLTemplateElement(commonAncestor->node())->content()->parserAppendChild(lastNode->element());
-            else
-                commonAncestor->node()->parserAppendChild(lastNode->element());
-            ASSERT(lastNode->stackItem()->isElementNode());
-            ASSERT(lastNode->element()->parentNode());
-            if (lastNode->element()->parentNode()->attached() && !lastNode->element()->attached())
-                lastNode->element()->lazyAttach();
-        }
+        m_tree.insertAlreadyParsedChild(commonAncestor.get(), lastNode);
         // 11.
         RefPtr<HTMLStackItem> newItem = m_tree.createElementFromSavedToken(formattingElementRecord->stackItem().get());
         // 12.
-        newItem->element()->takeAllChildrenFrom(furthestBlock->element());
+        m_tree.takeAllChildren(newItem.get(), furthestBlock);
         // 13.
-        Element* furthestBlockElement = furthestBlock->element();
-        // FIXME: All this creation / parserAppendChild / attach business should
-        //        be in HTMLConstructionSite. My guess is that steps 11--15
-        //        should all be in some HTMLConstructionSite function.
-        furthestBlockElement->parserAppendChild(newItem->element());
-        // FIXME: Why is this attach logic necessary? Style resolve should attach us if needed.
-        if (furthestBlockElement->attached() && !newItem->element()->attached()) {
-            // Notice that newItem->element() might already be attached if, for example, one of the reparented
-            // children is a style element, which attaches itself automatically.
-            newItem->element()->attach();
-        }
+        m_tree.reparent(furthestBlock, newItem.get());
         // 14.
         m_tree.activeFormattingElements()->swapTo(formattingElement, newItem, bookmark);
         // 15.