Make sure getAttribute() / setAttribute() callers use AtomicStrings

Source/core/html/HTMLMetaElement-in.cpp

Index: Source/core/html/HTMLMetaElement-in.cpp
diff --git a/Source/core/html/HTMLMetaElement-in.cpp b/Source/core/html/HTMLMetaElement-in.cpp
index 18697f4b4420fde18c11de22f4ee156c04c45e7b..c6347df23bfa2b2aea9e0797444fdc2f22f1389e 100644
--- a/Source/core/html/HTMLMetaElement-in.cpp
+++ b/Source/core/html/HTMLMetaElement-in.cpp
@@ -471,17 +471,17 @@ void HTMLMetaElement::process()
         processViewportContentAttribute("width=device-width, initial-scale=1", ViewportDescription::MobileOptimizedMeta);
 }
 
-String HTMLMetaElement::content() const
+const AtomicString& HTMLMetaElement::content() const
 {
     return getAttribute(contentAttr);
 }
 
-String HTMLMetaElement::httpEquiv() const
+const AtomicString& HTMLMetaElement::httpEquiv() const
 {
     return getAttribute(http_equivAttr);
 }
 
-String HTMLMetaElement::name() const
+const AtomicString& HTMLMetaElement::name() const
 {
     return getNameAttribute();
 }