Oilpan: promptly dispose style resolvers upon clearing.

third_party/WebKit/Source/core/css/resolver/StyleResolver.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/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 145 matching lines @@
         m_medium = adoptPtr(new MediaQueryEvaluator("all"));
     }
 
     initWatchedSelectorRules();
 }
 
 StyleResolver::~StyleResolver()
 {
 }
 
+void StyleResolver::dispose()
+{
+    m_features.clear();
+    if (m_siblingRuleSet) {
+        m_siblingRuleSet->dispose();
+        m_siblingRuleSet.clear();
+    }
+    if (m_uncommonAttributeRuleSet) {
+        m_uncommonAttributeRuleSet->dispose();
+        m_uncommonAttributeRuleSet.clear();
+    }
+    m_styleSharingLists.clear();
+    if (m_watchedSelectorsRules) {
+        m_watchedSelectorsRules->dispose();
+        m_watchedSelectorsRules.clear();
+    }
+    m_pendingStyleSheets.clear();
+}
+
 void StyleResolver::initWatchedSelectorRules()
 {
     CSSSelectorWatch* watch = CSSSelectorWatch::fromIfExists(*m_document);
     if (!watch)
         return;
     const WillBeHeapVector<RefPtrWillBeMember<StyleRule>>& watchedSelectors = watch->watchedCallbackSelectors();
     if (!watchedSelectors.size())
         return;
     m_watchedSelectorsRules = RuleSet::create();
     for (unsigned i = 0; i < watchedSelectors.size(); ++i)
@@ skipping 1278 matching lines @@
 
     for (CSSPropertyID property : properties) {
         if (property == CSSPropertyLineHeight)
             updateFont(state);
         StyleBuilder::applyProperty(property, state, propertySet.getPropertyCSSValue(property).get());
     }
 }
 
 void StyleResolver::addMediaQueryResults(const MediaQueryResultList& list)
 {
-    for (size_t i = 0; i < list.size(); ++i)
-        m_viewportDependentMediaQueryResults.append(list[i]);
+    if (list.size())
+        m_viewportDependentMediaQueryResults.appendVector(list);
 }
 
 bool StyleResolver::mediaQueryAffectedByViewportChange() const
 {
     for (unsigned i = 0; i < m_viewportDependentMediaQueryResults.size(); ++i) {
         if (m_medium->eval(m_viewportDependentMediaQueryResults[i]->expression()) != m_viewportDependentMediaQueryResults[i]->result())
             return true;
     }
     return false;
 }
@@ skipping 11 matching lines @@
     visitor->trace(m_watchedSelectorsRules);
     visitor->trace(m_treeBoundaryCrossingRules);
     visitor->trace(m_styleResourceLoader);
     visitor->trace(m_styleSharingLists);
     visitor->trace(m_pendingStyleSheets);
     visitor->trace(m_document);
 #endif
 }
 
 } // namespace blink