Added addXSLStyleSheet and removeXSLStyleSheet to StyleEngine.

Source/core/dom/ProcessingInstruction.cpp

Index: Source/core/dom/ProcessingInstruction.cpp
diff --git a/Source/core/dom/ProcessingInstruction.cpp b/Source/core/dom/ProcessingInstruction.cpp
index 59df65c9773d09395286a316cbb85d838c773867..a7d93d495715b45fc2e94075b9ebeb526a9d1213 100644
--- a/Source/core/dom/ProcessingInstruction.cpp
+++ b/Source/core/dom/ProcessingInstruction.cpp
@@ -59,8 +59,15 @@ ProcessingInstruction::~ProcessingInstruction()
     if (m_sheet)
         m_sheet->clearOwnerNode();
 
-    if (inDocument())
-        document().styleEngine()->removeStyleSheetCandidateNode(this);
+    // FIXME: ProcessingInstruction should not be in document here.
+    // However, if we add ASSERT(!inDocument()), fast/xsl/xslt-entity.xml
+    // crashes. We need to investigate ProcessingInstruction lifetime.
+    if (inDocument()) {
+        if (m_isCSS)
+            document().styleEngine()->removeStyleSheetCandidateNode(this);
+        else if (m_isXSL)
+            document().styleEngine()->removeXSLStyleSheet(this);
+    }
 #endif
 }
 
@@ -242,11 +249,11 @@ Node::InsertionNotificationRequest ProcessingInstruction::insertedInto(Container
 
     String href;
     String charset;
-    // To make it possible for us to see isXSL in
-    // StyleEngine::addStyleSheetCandidateNode, split checkStyleSheet
-    // into two methods, checkStyleSheet and process.
     bool isValid = checkStyleSheet(href, charset);
-    document().styleEngine()->addStyleSheetCandidateNode(this, m_createdByParser);
+    if (m_isCSS)
+        document().styleEngine()->addStyleSheetCandidateNode(this, m_createdByParser);
+    else if (m_isXSL)
+        document().styleEngine()->addXSLStyleSheet(this, m_createdByParser);
     if (isValid)
         process(href, charset);
     return InsertionDone;
@@ -258,7 +265,10 @@ void ProcessingInstruction::removedFrom(ContainerNode* insertionPoint)
     if (!insertionPoint->inDocument())
         return;
 
-    document().styleEngine()->removeStyleSheetCandidateNode(this);
+    if (m_isCSS)
+        document().styleEngine()->removeStyleSheetCandidateNode(this);
+    else if (m_isXSL)
+        document().styleEngine()->removeXSLStyleSheet(this);
 
     RefPtrWillBeRawPtr<StyleSheet> removedSheet = m_sheet;