Remove ~1750 superfluous includes from core

Source/core/dom/MutationObserverRegistration.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 
 #include "core/dom/MutationObserverRegistration.h"
 
-#include "core/dom/Document.h"
 #include "core/dom/Node.h"
 #include "core/dom/QualifiedName.h"
 
 namespace WebCore {
 
 PassOwnPtr<MutationObserverRegistration> MutationObserverRegistration::create(PassRefPtr<MutationObserver> observer, Node* registrationNode, MutationObserverOptions options, const HashSet<AtomicString>& attributeFilter)
 {
     return adoptPtr(new MutationObserverRegistration(observer, registrationNode, options, attributeFilter));
 }
 
@@ skipping 79 matching lines @@
 void MutationObserverRegistration::addRegistrationNodesToSet(HashSet<Node*>& nodes) const
 {
     nodes.add(m_registrationNode);
     if (!m_transientRegistrationNodes)
         return;
     for (NodeHashSet::const_iterator iter = m_transientRegistrationNodes->begin(); iter != m_transientRegistrationNodes->end(); ++iter)
         nodes.add(iter->get());
 }
 
 } // namespace WebCore