Split Dictionary's get and convert into DictionaryHelper.

Source/core/page/EventSource.cpp

Index: Source/core/page/EventSource.cpp
diff --git a/Source/core/page/EventSource.cpp b/Source/core/page/EventSource.cpp
index f63cc4a3b5b5e1eba2824440cd2195424cd3c253..7ba778cf6837f06b80e84fb680a1b6e072e723dc 100644
--- a/Source/core/page/EventSource.cpp
+++ b/Source/core/page/EventSource.cpp
@@ -34,6 +34,7 @@
 #include "core/page/EventSource.h"
 
 #include "bindings/core/v8/Dictionary.h"
+#include "bindings/core/v8/DictionaryHelper.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptController.h"
 #include "bindings/core/v8/SerializedScriptValue.h"
@@ -69,7 +70,7 @@ inline EventSource::EventSource(ExecutionContext* context, const KURL& url, cons
     , m_reconnectDelay(defaultReconnectDelay)
 {
     ScriptWrappable::init(this);
-    eventSourceInit.get("withCredentials", m_withCredentials);
+    DictionaryHelper::get(eventSourceInit, "withCredentials", m_withCredentials);
 }
 
 PassRefPtrWillBeRawPtr<EventSource> EventSource::create(ExecutionContext* context, const String& url, const Dictionary& eventSourceInit, ExceptionState& exceptionState)