Simpler return value from HashTable::add()/HashMap::add() and others

Source/core/xml/XMLHttpRequest.cpp

Index: Source/core/xml/XMLHttpRequest.cpp
diff --git a/Source/core/xml/XMLHttpRequest.cpp b/Source/core/xml/XMLHttpRequest.cpp
index ee407bcf459a6183fcf587a29e27176344d0836e..adf3672e675dccc01615b6823f02a4b75c75054f 100644
--- a/Source/core/xml/XMLHttpRequest.cpp
+++ b/Source/core/xml/XMLHttpRequest.cpp
@@ -1106,7 +1106,7 @@ void XMLHttpRequest::setRequestHeaderInternal(const AtomicString& name, const At
 {
     HTTPHeaderMap::AddResult result = m_requestHeaders.add(name, value);
     if (!result.isNewEntry)
-        result.iterator->value = result.iterator->value + ", " + value;
+        result.storedValue->value = result.storedValue->value + ", " + value;
 }
 
 const AtomicString& XMLHttpRequest::getRequestHeader(const AtomicString& name) const