Add Streams API support to XMLHttpRequest

Source/core/xml/XMLHttpRequest.h

Index: Source/core/xml/XMLHttpRequest.h
diff --git a/Source/core/xml/XMLHttpRequest.h b/Source/core/xml/XMLHttpRequest.h
index fde3a84be50dc828ba69a830a38d5149ddbab9f5..a3fdd134109e576ec38d7320ecc1c200fda914c3 100644
--- a/Source/core/xml/XMLHttpRequest.h
+++ b/Source/core/xml/XMLHttpRequest.h
@@ -46,6 +46,7 @@ class ExceptionState;
 class ResourceRequest;
 class SecurityOrigin;
 class SharedBuffer;
+class Stream;
 class TextResourceDecoder;
 class ThreadableLoader;
 
@@ -71,7 +72,8 @@ public:
         ResponseTypeText,
         ResponseTypeDocument,
         ResponseTypeBlob,
-        ResponseTypeArrayBuffer
+        ResponseTypeArrayBuffer,
+        ResponseTypeStream
     };
 
     virtual void contextDestroyed();
@@ -109,6 +111,7 @@ public:
     ScriptString responseText(ExceptionState&);
     Document* responseXML(ExceptionState&);
     Blob* responseBlob(ExceptionState&);
+    Stream* responseStream(ExceptionState&);
     unsigned long timeout() const { return m_timeoutMilliseconds; }
     void setTimeout(unsigned long timeout, ExceptionState&);
 
@@ -198,6 +201,7 @@ private:
     bool m_includeCredentials;
     unsigned long m_timeoutMilliseconds;
     RefPtr<Blob> m_responseBlob;
+    RefPtr<Stream> m_responseStream;
 
     RefPtr<ThreadableLoader> m_loader;
     State m_state;