Use new is*Element() helper functions in DOM code

Source/core/dom/StyleEngine.cpp

Index: Source/core/dom/StyleEngine.cpp
diff --git a/Source/core/dom/StyleEngine.cpp b/Source/core/dom/StyleEngine.cpp
index f59a38e203d880478af6b41ac56e4eeaad749b46..f5612f1b22c5de7aefda138e2b839eaffd8665b9 100644
--- a/Source/core/dom/StyleEngine.cpp
+++ b/Source/core/dom/StyleEngine.cpp
@@ -244,7 +244,8 @@ void StyleEngine::addPendingSheet()
 // This method is called whenever a top-level stylesheet has finished loading.
 void StyleEngine::removePendingSheet(Node* styleSheetCandidateNode, RemovePendingSheetNotificationType notification)
 {
-    TreeScope* treeScope = styleSheetCandidateNode->hasTagName(styleTag) ? &styleSheetCandidateNode->treeScope() : &m_document;
+    ASSERT(styleSheetCandidateNode);
+    TreeScope* treeScope = isHTMLStyleElement(*styleSheetCandidateNode) ? &styleSheetCandidateNode->treeScope() : &m_document;
     markTreeScopeDirty(*treeScope);
     master()->styleEngine()->notifyPendingStyleSheetRemoved(notification);
 }
@@ -284,8 +285,8 @@ void StyleEngine::modifiedStyleSheet(StyleSheet* sheet)
     if (!node || !node->inDocument())
         return;
 
-    TreeScope& treeScope = node->hasTagName(styleTag) ? node->treeScope() : m_document;
-    ASSERT(node->hasTagName(styleTag) || treeScope == m_document);
+    TreeScope& treeScope = isHTMLStyleElement(*node) ? node->treeScope() : m_document;
+    ASSERT(isHTMLStyleElement(node) || treeScope == m_document);
 
     markTreeScopeDirty(treeScope);
 }
@@ -295,8 +296,8 @@ void StyleEngine::addStyleSheetCandidateNode(Node* node, bool createdByParser)
     if (!node->inDocument())
         return;
 
-    TreeScope& treeScope = node->hasTagName(styleTag) ? node->treeScope() : m_document;
-    ASSERT(node->hasTagName(styleTag) || treeScope == m_document);
+    TreeScope& treeScope = isHTMLStyleElement(*node) ? node->treeScope() : m_document;
+    ASSERT(isHTMLStyleElement(node) || treeScope == m_document);
 
     TreeScopeStyleSheetCollection* collection = ensureStyleSheetCollectionFor(treeScope);
     ASSERT(collection);
@@ -310,7 +311,7 @@ void StyleEngine::addStyleSheetCandidateNode(Node* node, bool createdByParser)
 void StyleEngine::removeStyleSheetCandidateNode(Node* node, ContainerNode* scopingNode)
 {
     TreeScope& treeScope = scopingNode ? scopingNode->treeScope() : m_document;
-    ASSERT(node->hasTagName(styleTag) || treeScope == m_document);
+    ASSERT(isHTMLStyleElement(node) || treeScope == m_document);
 
     TreeScopeStyleSheetCollection* collection = styleSheetCollectionFor(treeScope);
     ASSERT(collection);
@@ -325,8 +326,8 @@ void StyleEngine::modifiedStyleSheetCandidateNode(Node* node)
     if (!node->inDocument())
         return;
 
-    TreeScope& treeScope = node->hasTagName(styleTag) ? node->treeScope() : m_document;
-    ASSERT(node->hasTagName(styleTag) || treeScope == m_document);
+    TreeScope& treeScope = isHTMLStyleElement(*node) ? node->treeScope() : m_document;
+    ASSERT(isHTMLStyleElement(node) || treeScope == m_document);
     markTreeScopeDirty(treeScope);
 }