Rename ElementData's attribute related methods for clarity

Source/core/dom/Element.h

Index: Source/core/dom/Element.h
diff --git a/Source/core/dom/Element.h b/Source/core/dom/Element.h
index 4574822f3d3fa2687babc827fe3b811d472aba15..3d86958fce1e0c97c37a260bfeb6e13d3d034585 100644
--- a/Source/core/dom/Element.h
+++ b/Source/core/dom/Element.h
@@ -171,10 +171,10 @@ public:
     // performance.
     AttributeIteratorAccessor attributesIterator() const { return elementData()->attributesIterator(); }
     size_t attributeCount() const;
-    const Attribute& attributeItem(unsigned index) const;
-    const Attribute* getAttributeItem(const QualifiedName&) const;
-    size_t getAttributeItemIndex(const QualifiedName& name) const { return elementData()->getAttributeItemIndex(name); }
-    size_t getAttributeItemIndex(const AtomicString& name, bool shouldIgnoreAttributeCase) const { return elementData()->getAttributeItemIndex(name, shouldIgnoreAttributeCase); }
+    const Attribute& attributeAt(unsigned index) const;
+    const Attribute* findAttributeByName(const QualifiedName&) const;
+    size_t findAttributeIndexByName(const QualifiedName& name) const { return elementData()->findAttributeIndexByName(name); }
+    size_t findAttributeIndexByName(const AtomicString& name, bool shouldIgnoreAttributeCase) const { return elementData()->findAttributeIndexByName(name, shouldIgnoreAttributeCase); }
 
     void scrollIntoView(bool alignToTop = true);
     void scrollIntoViewIfNeeded(bool centerIfNeeded = true);
@@ -602,7 +602,7 @@ private:
     virtual bool childTypeAllowed(NodeType) const OVERRIDE FINAL;
 
     void setAttributeInternal(size_t index, const QualifiedName&, const AtomicString& value, SynchronizationOfLazyAttribute);
-    void addAttributeInternal(const QualifiedName&, const AtomicString& value, SynchronizationOfLazyAttribute);
+    void appendAttributeInternal(const QualifiedName&, const AtomicString& value, SynchronizationOfLazyAttribute);
     void removeAttributeInternal(size_t index, SynchronizationOfLazyAttribute);
     void attributeChangedFromParserOrByCloning(const QualifiedName&, const AtomicString&, AttributeModificationReason);
 
@@ -695,14 +695,14 @@ inline Element* Node::parentElement() const
 inline bool Element::fastHasAttribute(const QualifiedName& name) const
 {
     ASSERT(fastAttributeLookupAllowed(name));
-    return elementData() && getAttributeItem(name);
+    return elementData() && findAttributeByName(name);
 }
 
 inline const AtomicString& Element::fastGetAttribute(const QualifiedName& name) const
 {
     ASSERT(fastAttributeLookupAllowed(name));
     if (elementData()) {
-        if (const Attribute* attribute = getAttributeItem(name))
+        if (const Attribute* attribute = findAttributeByName(name))
             return attribute->value();
     }
     return nullAtom;
@@ -710,7 +710,7 @@ inline const AtomicString& Element::fastGetAttribute(const QualifiedName& name)
 
 inline bool Element::hasAttributesWithoutUpdate() const
 {
-    return elementData() && !elementData()->isEmpty();
+    return elementData() && elementData()->hasAttributes();
 }
 
 inline const AtomicString& Element::idForStyleResolution() const
@@ -767,19 +767,19 @@ inline const SpaceSplitString& Element::classNames() const
 inline size_t Element::attributeCount() const
 {
     ASSERT(elementData());
-    return elementData()->length();
+    return elementData()->attributeCount();
 }
 
-inline const Attribute& Element::attributeItem(unsigned index) const
+inline const Attribute& Element::attributeAt(unsigned index) const
 {
     ASSERT(elementData());
-    return elementData()->attributeItem(index);
+    return elementData()->attributeAt(index);
 }
 
-inline const Attribute* Element::getAttributeItem(const QualifiedName& name) const
+inline const Attribute* Element::findAttributeByName(const QualifiedName& name) const
 {
     ASSERT(elementData());
-    return elementData()->getAttributeItem(name);
+    return elementData()->findAttributeByName(name);
 }
 
 inline bool Element::hasID() const