Don't include LayoutObject-derived headers where not needed.

third_party/WebKit/Source/core/css/SelectorChecker.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc.
  * All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
@@ skipping 35 matching lines @@
 #include "core/frame/LocalFrame.h"
 #include "core/html/HTMLDocument.h"
 #include "core/html/HTMLFrameElementBase.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/html/HTMLOptionElement.h"
 #include "core/html/HTMLSelectElement.h"
 #include "core/html/HTMLSlotElement.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 #include "core/html/track/vtt/VTTElement.h"
 #include "core/inspector/InspectorInstrumentation.h"
-#include "core/layout/LayoutObject.h"
-#include "core/layout/LayoutScrollbar.h"
 #include "core/page/FocusController.h"
 #include "core/page/Page.h"
 #include "core/style/ComputedStyle.h"
 #include "platform/scroll/ScrollableArea.h"
 #include "platform/scroll/ScrollbarTheme.h"
 #include "wtf/AutoReset.h"
 
 namespace blink {
 
 using namespace HTMLNames;
@@ skipping 1202 matching lines @@
 }
 
 bool SelectorChecker::matchesFocusPseudoClass(const Element& element) {
   if (InspectorInstrumentation::forcePseudoState(const_cast<Element*>(&element),
                                                  CSSSelector::PseudoFocus))
     return true;
   return element.isFocused() && isFrameFocused(element);
 }
 
 }  // namespace blink