Delete the Layer Squashing runtime feature.

Source/web/WebSettingsImpl.cpp

 /*
  * Copyright (C) 2009 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 529 matching lines @@
 void WebSettingsImpl::setMinimumAccelerated2dCanvasSize(int numPixels)
 {
     m_settings->setMinimumAccelerated2dCanvasSize(numPixels);
 }
 
 void WebSettingsImpl::setHyperlinkAuditingEnabled(bool enabled)
 {
     m_settings->setHyperlinkAuditingEnabled(enabled);
 }
 
-void WebSettingsImpl::setLayerSquashingEnabled(bool enabled)
-{
-    m_settings->setLayerSquashingEnabled(enabled);
-}
-
 void WebSettingsImpl::setAsynchronousSpellCheckingEnabled(bool enabled)
 {
     m_settings->setAsynchronousSpellCheckingEnabled(enabled);
 }
 
 void WebSettingsImpl::setUnifiedTextCheckerEnabled(bool enabled)
 {
     m_settings->setUnifiedTextCheckerEnabled(enabled);
 }
 
@@ skipping 186 matching lines @@
 {
     m_settings->setV8ScriptStreamingEnabled(enabled);
 }
 
 void WebSettingsImpl::setV8ScriptStreamingMode(V8ScriptStreamingMode mode)
 {
     m_settings->setV8ScriptStreamingMode(static_cast<blink::ScriptStreamingMode>(mode));
 }
 
 } // namespace blink