Make calls to AtomicString(const String&) explicit in dom/

Source/core/dom/DatasetDOMStringMap.cpp

Index: Source/core/dom/DatasetDOMStringMap.cpp
diff --git a/Source/core/dom/DatasetDOMStringMap.cpp b/Source/core/dom/DatasetDOMStringMap.cpp
index 921531948ca49d0f372263ce1972af4b43334950..ae798de84bf43709e3e4bd740c1f191ffcc6c7bd 100644
--- a/Source/core/dom/DatasetDOMStringMap.cpp
+++ b/Source/core/dom/DatasetDOMStringMap.cpp
@@ -107,7 +107,7 @@ static bool isValidPropertyName(const String& name)
     return true;
 }
 
-static String convertPropertyNameToAttributeName(const String& name)
+static AtomicString convertPropertyNameToAttributeName(const String& name)
 {
     StringBuilder builder;
     builder.append("data-");
@@ -122,7 +122,7 @@ static String convertPropertyNameToAttributeName(const String& name)
             builder.append(character);
     }
 
-    return builder.toString();
+    return builder.toAtomicString();
 }
 
 void DatasetDOMStringMap::ref()
@@ -185,7 +185,7 @@ void DatasetDOMStringMap::setItem(const String& name, const String& value, Excep
         return;
     }
 
-    m_element->setAttribute(convertPropertyNameToAttributeName(name), value, exceptionState);
+    m_element->setAttribute(convertPropertyNameToAttributeName(name), AtomicString(value), exceptionState);
 }
 
 void DatasetDOMStringMap::deleteItem(const String& name, ExceptionState& exceptionState)