PurgeMemory.

third_party/WebKit/Source/core/dom/StyleEngine.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 706 matching lines @@
     if (!enabled) {
         m_styleResolverStats = nullptr;
         return;
     }
     if (!m_styleResolverStats)
         m_styleResolverStats = StyleResolverStats::create();
     else
         m_styleResolverStats->reset();
 }
 
+void StyleEngine::purgeMemory(DeviceKind deviceKind)
+{
+    if (m_documentStyleSheetCollection)
+        m_documentStyleSheetCollection->purgeMemory();
+    for (ShadowTreeStyleSheetCollection* collection : m_styleSheetCollectionMap.values())
+        collection->purgeMemory();
+    clearFontCache();
+    clearResolver();
+    m_textToSheetCache.clear();
+    m_sheetToTextCache.clear();
+}
+
 DEFINE_TRACE(StyleEngine)
 {
 #if ENABLE(OILPAN)
     visitor->trace(m_document);
     visitor->trace(m_injectedAuthorStyleSheets);
     visitor->trace(m_documentStyleSheetCollection);
     visitor->trace(m_styleSheetCollectionMap);
     visitor->trace(m_resolver);
     visitor->trace(m_styleInvalidator);
     visitor->trace(m_dirtyTreeScopes);
     visitor->trace(m_activeTreeScopes);
     visitor->trace(m_fontSelector);
     visitor->trace(m_textToSheetCache);
     visitor->trace(m_sheetToTextCache);
 #endif
     CSSFontSelectorClient::trace(visitor);
 }
 
 } // namespace blink