Added addXSLStyleSheet and removeXSLStyleSheet to StyleEngine.

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 57 matching lines @@
     , m_usesSiblingRulesOverride(false)
     , m_usesFirstLineRules(false)
     , m_usesFirstLetterRules(false)
     , m_usesRemUnits(false)
     , m_maxDirectAdjacentSelectors(0)
     , m_ignorePendingStylesheets(false)
     , m_didCalculateResolver(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_xslStyleSheet(nullptr)
 {
     if (m_fontSelector)
         m_fontSelector->registerForInvalidationCallbacks(this);
 }
 
 StyleEngine::~StyleEngine()
 {
 }
 
 #if !ENABLE(OILPAN)
@@ skipping 191 matching lines @@
     markTreeScopeDirty(treeScope);
 }
 
 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);
-
+    ASSERT(!isXSLStyleSheet(*node));
     TreeScopeStyleSheetCollection* collection = ensureStyleSheetCollectionFor(treeScope);
     ASSERT(collection);
     collection->addStyleSheetCandidateNode(node, createdByParser);
 
     markTreeScopeDirty(treeScope);
     if (treeScope != m_document)
         insertTreeScopeInDocumentOrder(m_activeTreeScopes, &treeScope);
 }
 
 void StyleEngine::removeStyleSheetCandidateNode(Node* node)
 {
     removeStyleSheetCandidateNode(node, 0, *m_document);
 }
 
 void StyleEngine::removeStyleSheetCandidateNode(Node* node, ContainerNode* scopingNode, TreeScope& treeScope)
 {
     ASSERT(isHTMLStyleElement(node) || treeScope == m_document);
+    ASSERT(!isXSLStyleSheet(*node));
 
     TreeScopeStyleSheetCollection* collection = styleSheetCollectionFor(treeScope);
     ASSERT(collection);
     collection->removeStyleSheetCandidateNode(node, scopingNode);
 
     markTreeScopeDirty(treeScope);
     m_activeTreeScopes.remove(&treeScope);
 }
 
+void StyleEngine::addXSLStyleSheet(ProcessingInstruction* node, bool createdByParser)
+{
+    if (!node->inDocument())
+        return;
+
+    ASSERT(isXSLStyleSheet(*node));
+    bool needToUpdate = false;
+    if (createdByParser || !m_xslStyleSheet) {
+        needToUpdate = !m_xslStyleSheet;
+    } else {
+        unsigned position = m_xslStyleSheet->compareDocumentPositionInternal(node, Node::TreatShadowTreesAsDisconnected);
+        needToUpdate = position & Node::DOCUMENT_POSITION_FOLLOWING;
+    }
+
+    if (!needToUpdate)
+        return;
+
+    markTreeScopeDirty(*m_document);
+    m_xslStyleSheet = node;
+}
+
+void StyleEngine::removeXSLStyleSheet(ProcessingInstruction* node)
+{
+    ASSERT(isXSLStyleSheet(*node));
+    if (m_xslStyleSheet != node)
+        return;
+
+    markTreeScopeDirty(*m_document);
+    m_xslStyleSheet = nullptr;
+}
+
 void StyleEngine::modifiedStyleSheetCandidateNode(Node* node)
 {
     if (!node->inDocument())
         return;
 
     TreeScope& treeScope = isHTMLStyleElement(*node) ? node->treeScope() : *m_document;
     ASSERT(isHTMLStyleElement(node) || treeScope == m_document);
     markTreeScopeDirty(treeScope);
 }
 
@@ skipping 154 matching lines @@
 void StyleEngine::didDetach()
 {
     clearResolver();
 }
 
 bool StyleEngine::shouldClearResolver() const
 {
     return !m_didCalculateResolver && !haveStylesheetsLoaded();
 }
 
+bool StyleEngine::shouldApplyXSLTransform() const
+{
+    if (!RuntimeEnabledFeatures::xsltEnabled())
+        return false;
+    return m_xslStyleSheet && !m_document->transformSourceDocument();
+}
+
 StyleResolverChange StyleEngine::resolverChanged(StyleResolverUpdateMode mode)
 {
     StyleResolverChange change;
 
     if (!isMaster()) {
         if (Document* master = this->master())
             master->styleResolverChanged(mode);
         return change;
     }
 
     // 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 (!document().isActive() || shouldClearResolver()) {
         clearResolver();
         return change;
     }
 
+    if (shouldApplyXSLTransform()) {
+        // Processing instruction (XML documents only).
+        // We don't support linking to embedded CSS stylesheets, see <https://bugs.webkit.org/show_bug.cgi?id=49281> for discussion.
+        // Don't apply XSL transforms to already transformed documents -- <rdar://problem/4132806>
+        if (!m_document->parsing() && !m_xslStyleSheet->isLoading())
+            m_document->applyXSLTransform(m_xslStyleSheet.get());
+        return change;
+    }
+
     m_didCalculateResolver = true;
     if (document().didLayoutWithPendingStylesheets() && !hasPendingSheets())
         change.setNeedsRepaint();
 
     if (updateActiveStyleSheets(mode))
         change.setNeedsStyleRecalc();
 
     return change;
 }
 
@@ skipping 129 matching lines @@
     visitor->trace(m_documentStyleSheetCollection);
     visitor->trace(m_styleSheetCollectionMap);
     visitor->trace(m_resolver);
     visitor->trace(m_fontSelector);
     visitor->trace(m_textToSheetCache);
     visitor->trace(m_sheetToTextCache);
     CSSFontSelectorClient::trace(visitor);
 }
 
 }