Factor out delivery of throttled progress event.

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 4b56fcef3fbbd94b89a7fa45a3ca11b2c808f1d0..8814031fc868047dd6d0b42aa09cf90f369e378f 100644
--- a/Source/core/xml/XMLHttpRequest.h
+++ b/Source/core/xml/XMLHttpRequest.h
@@ -187,6 +187,9 @@ private:
     // Dispatches an event of the specified type to m_upload and
     // m_progressEventThrottle.
     void dispatchEventAndLoadEnd(const AtomicString&);
+
+    void dispatchThrottledProgressEvent();
+
     // Does clean up common for all kind of didFail() call.
     void handleDidFailGeneric();
     // Handles didFail() call not caused by cancellation or timeout.