Include HTMLFrameOwnerElement.h in fewer headers

Source/core/dom/ChildFrameDisconnector.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/dom/ChildFrameDisconnector.h"
 
 #include "core/dom/shadow/ElementShadow.h"
 #include "core/dom/shadow/ShadowRoot.h"
+#include "core/html/HTMLFrameOwnerElement.h"
 #include "wtf/Assertions.h"
 
 namespace WebCore {
 
 #ifndef NDEBUG
 static unsigned checkConnectedSubrameCountIsConsistent(Node&);
 #endif
 
 void ChildFrameDisconnector::disconnect(DisconnectPolicy policy)
 {
@@ skipping 76 matching lines @@
     // If we overcount it's safe, but not optimal because it means we'll traverse
     // through the document in ChildFrameDisconnector looking for frames that have
     // already been disconnected.
     ASSERT(node.connectedSubframeCount() == count);
 
     return count;
 }
 #endif
 
 }