Simplify StyleEngine clean up.

sky/engine/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 29 matching lines @@
 #include "sky/engine/core/frame/Settings.h"
 #include "sky/engine/core/html/HTMLStyleElement.h"
 #include "sky/engine/core/html/imports/HTMLImportsController.h"
 #include "sky/engine/core/page/Page.h"
 
 namespace blink {
 
 StyleEngine::StyleEngine(Document& document)
     : m_document(&document)
     , m_ignorePendingStylesheets(false)
-    // We don't need to create CSSFontSelector for imported document or
-    // HTMLTemplateElement's document, because those documents have no frame.
-    , m_fontSelector(document.frame() ? CSSFontSelector::create(&document) : nullptr)
+    , m_fontSelector(CSSFontSelector::create(&document))
 {
-    if (m_fontSelector)
-        m_fontSelector->registerForInvalidationCallbacks(this);
+    m_fontSelector->registerForInvalidationCallbacks(this);
 }
 
 StyleEngine::~StyleEngine()
 {
-}
-
-void StyleEngine::detachFromDocument()
-{
-    // Cleanup is performed eagerly when the StyleEngine is removed from the
-    // document. The StyleEngine is unreachable after this, since only the
-    // document has a reference to it.
-
-    if (m_fontSelector) {
-        m_fontSelector->clearDocument();
-        m_fontSelector->unregisterForInvalidationCallbacks(this);
-    }
-
-    // Decrement reference counts for things we could be keeping alive.
-    m_fontSelector.clear();
-    m_resolver.clear();
+    m_fontSelector->clearDocument();
+    m_fontSelector->unregisterForInvalidationCallbacks(this);
 }
 
 void StyleEngine::addStyleSheetCandidateNode(Node* node, bool createdByParser)
 {
     if (!node->inDocument())
         return;
 
     TreeScope& treeScope = isHTMLStyleElement(*node) ? node->treeScope() : *m_document;
     ASSERT(isHTMLStyleElement(node) || treeScope == m_document);
     StyleSheetCollection& collection = treeScope.styleSheets();
@@ skipping 65 matching lines @@
 {
     ASSERT(!m_document->inStyleRecalc());
     m_resolver.clear();
 }
 
 unsigned StyleEngine::resolverAccessCount() const
 {
     return m_resolver ? m_resolver->accessCount() : 0;
 }
 
-void StyleEngine::didDetach()
-{
-    clearResolver();
-}
-
 void StyleEngine::resolverChanged()
 {
     // Don't bother updating, since we haven't loaded all our style info yet
     // and haven't calculated the style selector for the first time.
     if (!m_document->isActive()) {
         clearResolver();
         return;
     }
 
     updateActiveStyleSheets();
 }
 
 void StyleEngine::clearFontCache()
 {
-    if (m_fontSelector)
-        m_fontSelector->fontFaceCache()->clearCSSConnected();
+    m_fontSelector->fontFaceCache()->clearCSSConnected();
     if (m_resolver)
         m_resolver->invalidateMatchedPropertiesCache();
 }
 
 void StyleEngine::updateGenericFontFamilySettings()
 {
     // FIXME: we should not update generic font family settings when
     // document is inactive.
     ASSERT(m_document->isActive());
 
-    if (!m_fontSelector)
-        return;
-
     m_fontSelector->updateGenericFontFamilySettings(*m_document);
     if (m_resolver)
         m_resolver->invalidateMatchedPropertiesCache();
 }
 
 void StyleEngine::removeFontFaceRules(const Vector<RawPtr<const StyleRuleFontFace> >& fontFaceRules)
 {
-    if (!m_fontSelector)
-        return;
-
     FontFaceCache* cache = m_fontSelector->fontFaceCache();
     for (unsigned i = 0; i < fontFaceRules.size(); ++i)
         cache->remove(fontFaceRules[i]);
     if (m_resolver)
         m_resolver->invalidateMatchedPropertiesCache();
 }
 
 PassRefPtr<CSSStyleSheet> StyleEngine::createSheet(Element* e, const String& text)
 {
     RefPtr<CSSStyleSheet> styleSheet;
@@ skipping 45 matching lines @@
 }
 
 void StyleEngine::fontsNeedUpdate(CSSFontSelector*)
 {
     if (m_resolver)
         m_resolver->invalidateMatchedPropertiesCache();
     m_document->setNeedsStyleRecalc(SubtreeStyleChange);
 }
 
 }