Use "unsigned" rather than "unsigned long" for C++ code interacting with WebIDL's "unsigned long".

Source/core/xmlhttprequest/XMLHttpRequest.cpp

Index: Source/core/xmlhttprequest/XMLHttpRequest.cpp
diff --git a/Source/core/xmlhttprequest/XMLHttpRequest.cpp b/Source/core/xmlhttprequest/XMLHttpRequest.cpp
index 3494b56af08c4942c249daae0482aed15b8680bc..1459bd2361f3ac24727f1d51eae5a00cef0e1f53 100644
--- a/Source/core/xmlhttprequest/XMLHttpRequest.cpp
+++ b/Source/core/xmlhttprequest/XMLHttpRequest.cpp
@@ -383,7 +383,7 @@ ReadableStream* XMLHttpRequest::responseStream()
     return m_responseStream;
 }
 
-void XMLHttpRequest::setTimeout(unsigned long timeout, ExceptionState& exceptionState)
+void XMLHttpRequest::setTimeout(unsigned timeout, ExceptionState& exceptionState)
 {
     // FIXME: Need to trigger or update the timeout Timer here, if needed. http://webkit.org/b/98156
     // XHR2 spec, 4.7.3. "This implies that the timeout attribute can be set while fetching is in progress. If that occurs it will still be measured relative to the start of fetching."