Move some Element specific code from Node::detach to Element::detach.

Source/core/dom/Element.cpp

Index: Source/core/dom/Element.cpp
diff --git a/Source/core/dom/Element.cpp b/Source/core/dom/Element.cpp
index d46c3733e5e6d7cae08c11b749ad60b93d48d4e9..41728e49b6bd6b0d788e8ce01e7e2b43cc4e8618 100644
--- a/Source/core/dom/Element.cpp
+++ b/Source/core/dom/Element.cpp
@@ -1503,9 +1503,20 @@ void Element::detach(const AttachContext& context)
 
     ContainerNode::detach(context);
 
-    ASSERT(needsAttach());
+    if (!context.performingReattach && isUserActionElement()) {
+        if (hovered())
+            document().hoveredNodeDetached(*this);
+        if (inActiveChain())
+            document().activeChainNodeDetached(*this);
+        document().userActionElements().didDetach(*this);
+    }
+
+    document().styleEngine().styleInvalidator().clearInvalidation(*this);
+
     if (svgFilterNeedsLayerUpdate())
         document().unscheduleSVGFilterLayerUpdateHack(*this);
+
+    ASSERT(needsAttach());
 }
 
 bool Element::pseudoStyleCacheIsInvalid(const ComputedStyle* currentStyle, ComputedStyle* newStyle)