Make Element::attributes() less error-prone and simplify call sites

Source/core/dom/Element.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 413 matching lines @@
         // true.
         toSVGElement(this)->synchronizeAnimatedSVGAttribute(QualifiedName(nullAtom, localName, nullAtom));
     }
 }
 
 const AtomicString& Element::getAttribute(const QualifiedName& name) const
 {
     if (!elementData())
         return nullAtom;
     synchronizeAttribute(name);
-    if (const Attribute* attribute = attributes().find(name))
+    if (const Attribute* attribute = elementData()->attributes().find(name))
         return attribute->value();
     return nullAtom;
 }
 
 bool Element::shouldIgnoreAttributeCase() const
 {
     return isHTMLElement() && document().isHTMLDocument();
 }
 
 void Element::scrollIntoView(bool alignToTop)
@@ skipping 458 matching lines @@
         if (index != kNotFound)
             removeAttributeInternal(index, inSynchronizationOfLazyAttribute);
         return;
     }
 
     if (index == kNotFound) {
         appendAttributeInternal(name, newValue, inSynchronizationOfLazyAttribute);
         return;
     }
 
-    const Attribute& existingAttribute = attributes().at(index);
+    const Attribute& existingAttribute = elementData()->attributes().at(index);
     QualifiedName existingAttributeName = existingAttribute.name();
 
     if (!inSynchronizationOfLazyAttribute)
         willModifyAttribute(existingAttributeName, existingAttribute.value(), newValue);
 
     if (newValue != existingAttribute.value()) {
         // If there is an Attr node hooked to this attribute, the Attr::setValue() call below
         // will write into the ElementData.
         // FIXME: Refactor this so it makes some sense.
         if (RefPtrWillBeRawPtr<Attr> attrNode = inSynchronizationOfLazyAttribute ? nullptr : attrIfExists(existingAttributeName))
@@ skipping 204 matching lines @@
     if (document().elementDataCache())
         m_elementData = document().elementDataCache()->cachedShareableElementDataWithAttributes(attributeVector);
     else
         m_elementData = ShareableElementData::createWithAttributes(attributeVector);
 
     // Use attributeVector instead of m_elementData because attributeChanged might modify m_elementData.
     for (unsigned i = 0; i < attributeVector.size(); ++i)
         attributeChangedFromParserOrByCloning(attributeVector[i].name(), attributeVector[i].value(), ModifiedDirectly);
 }
 
-bool Element::hasAttributes() const
-{
-    synchronizeAllAttributes();
-    return elementData() && !elementData()->attributes().isEmpty();
-}
-
 bool Element::hasEquivalentAttributes(const Element* other) const
 {
     synchronizeAllAttributes();
     other->synchronizeAllAttributes();
     if (elementData() == other->elementData())
         return true;
     if (elementData())
         return elementData()->isEquivalent(other->elementData());
     if (other->elementData())
         return other->elementData()->isEquivalent(elementData());
@@ skipping 31 matching lines @@
         return;
 
     m_tagName.setPrefix(prefix.isEmpty() ? AtomicString() : prefix);
 }
 
 const AtomicString& Element::locateNamespacePrefix(const AtomicString& namespaceToLocate) const
 {
     if (!prefix().isNull() && namespaceURI() == namespaceToLocate)
         return prefix();
 
-    if (hasAttributes()) {
-        AttributeCollection attributes = this->attributes();
-        AttributeCollection::const_iterator end = attributes.end();
-        for (AttributeCollection::const_iterator it = attributes.begin(); it != end; ++it) {
-            if (it->prefix() == xmlnsAtom && it->value() == namespaceToLocate)
-                return it->localName();
-        }
+    AttributeCollection attributes = this->attributes();
+    AttributeCollection::const_iterator end = attributes.end();
+    for (AttributeCollection::const_iterator it = attributes.begin(); it != end; ++it) {
+        if (it->prefix() == xmlnsAtom && it->value() == namespaceToLocate)
+            return it->localName();
     }
 
     if (Element* parent = parentElement())
         return parent->locateNamespacePrefix(namespaceToLocate);
 
     return nullAtom;
 }
 
 KURL Element::baseURI() const
 {
@@ skipping 1750 matching lines @@
         }
     }
     ASSERT_NOT_REACHED();
 }
 
 void Element::detachAllAttrNodesFromElement()
 {
     AttrNodeList* list = this->attrNodeList();
     ASSERT(list);
 
-    AttributeCollection attributes = this->attributes();
+    AttributeCollection attributes = elementData()->attributes();
     AttributeCollection::const_iterator end = attributes.end();
     for (AttributeCollection::const_iterator it = attributes.begin(); it != end; ++it) {
         if (RefPtrWillBeRawPtr<Attr> attrNode = findAttrNodeInList(*list, it->name()))
             attrNode->detachFromElementWithValue(it->value());
     }
 
     removeAttrNodeList();
 }
 
 void Element::willRecalcStyle(StyleRecalcChange)
@@ skipping 293 matching lines @@
 {
 #if ENABLE(OILPAN)
     if (hasRareData())
         visitor->trace(elementRareData());
     visitor->trace(m_elementData);
 #endif
     ContainerNode::trace(visitor);
 }
 
 } // namespace blink