Remove platform dependency upon page/Settings class which is a layering violation.

Source/core/page/Settings.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2011, 2012 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 17 matching lines @@
 
 #include <limits>
 #include "core/dom/Document.h"
 #include "core/fetch/ResourceFetcher.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/page/Chrome.h"
 #include "core/page/Frame.h"
 #include "core/page/FrameTree.h"
 #include "core/page/FrameView.h"
 #include "core/page/Page.h"
+#include "core/platform/ScrollbarTheme.h"
 #include "core/rendering/TextAutosizer.h"
 
 using namespace std;
 
 namespace WebCore {
 
 static void setImageLoadingSettings(Page* page)
 {
     for (Frame* frame = page->mainFrame(); frame; frame = frame->tree()->traverseNext()) {
         frame->document()->fetcher()->setImagesEnabled(page->settings().areImagesEnabled());
@@ skipping 21 matching lines @@
 static inline const AtomicString& getGenericFontFamilyForScript(const ScriptFontFamilyMap& fontMap, UScriptCode script)
 {
     ScriptFontFamilyMap::const_iterator it = fontMap.find(static_cast<int>(script));
     if (it != fontMap.end())
         return it->value;
     if (script != USCRIPT_COMMON)
         return getGenericFontFamilyForScript(fontMap, USCRIPT_COMMON);
     return emptyAtom;
 }
 
-bool Settings::gMockScrollbarsEnabled = false;
-
 // NOTEs
 //  1) EditingMacBehavior comprises builds on Mac;
 //  2) EditingWindowsBehavior comprises builds on Windows;
 //  3) EditingUnixBehavior comprises all unix-based systems, but Darwin/MacOS/Android (and then abusing the terminology);
 //  4) EditingAndroidBehavior comprises Android builds.
 // 99) MacEditingBehavior is used a fallback.
 static EditingBehaviorType editingBehaviorTypeForPlatform()
 {
     return
 #if OS(MACOSX)
@@ skipping 248 matching lines @@
 {
     if (m_dnsPrefetchingEnabled == dnsPrefetchingEnabled)
         return;
 
     m_dnsPrefetchingEnabled = dnsPrefetchingEnabled;
     m_page->dnsPrefetchingStateChanged();
 }
 
 void Settings::setMockScrollbarsEnabled(bool flag)
 {
-    gMockScrollbarsEnabled = flag;
+    ScrollbarTheme::setMockScrollbarsEnabled(flag);
 }
 
 bool Settings::mockScrollbarsEnabled()
 {
-    return gMockScrollbarsEnabled;
+    return ScrollbarTheme::mockScrollbarsEnabled();
 }
 
 void Settings::setOpenGLMultisamplingEnabled(bool flag)
 {
     if (m_openGLMultisamplingEnabled == flag)
         return;
 
     m_openGLMultisamplingEnabled = flag;
     m_page->multisamplingChanged();
 }
 
 bool Settings::openGLMultisamplingEnabled()
 {
     return m_openGLMultisamplingEnabled;
 }
 
 void Settings::setViewportEnabled(bool enabled)
 {
     if (m_viewportEnabled == enabled)
         return;
 
     m_viewportEnabled = enabled;
     if (m_page->mainFrame())
         m_page->mainFrame()->document()->updateViewportDescription();
 }
 
 } // namespace WebCore