Add Blink-side flag for enabling/disabling layer squashing.

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 546 matching lines @@
 void WebSettingsImpl::setMemoryInfoEnabled(bool enabled)
 {
     m_settings->setMemoryInfoEnabled(enabled);
 }
 
 void WebSettingsImpl::setHyperlinkAuditingEnabled(bool enabled)
 {
     m_settings->setHyperlinkAuditingEnabled(enabled);
 }
 
+void WebSettingsImpl::setLayerSquashingEnabled(bool enabled)
+{
+    m_settings->setLayerSquashingEnabled(enabled);
+}
+
 void WebSettingsImpl::setLayoutFallbackWidth(int width)
 {
     m_settings->setLayoutFallbackWidth(width);
 }
 
 void WebSettingsImpl::setAsynchronousSpellCheckingEnabled(bool enabled)
 {
     m_settings->setAsynchronousSpellCheckingEnabled(enabled);
 }
 
@@ skipping 189 matching lines @@
 {
     m_settings->setUseSolidColorScrollbars(enabled);
 }
 
 void WebSettingsImpl::setMainFrameResizesAreOrientationChanges(bool enabled)
 {
     m_mainFrameResizesAreOrientationChanges = enabled;
 }
 
 } // namespace blink