[XMLHttpRequest] Stop throwing for network error in async mode

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 d75347048676b26e778a719d20662e096684f8ac..393540ad6b53b2c57e9877e20ca66a4146efba83 100644
--- a/Source/core/xmlhttprequest/XMLHttpRequest.cpp
+++ b/Source/core/xmlhttprequest/XMLHttpRequest.cpp
@@ -1072,12 +1072,12 @@ void XMLHttpRequest::createRequest(PassRefPtr<FormData> httpBody, ExceptionState
         // Use count for XHR synchronous requests.
         UseCounter::count(&executionContext, UseCounter::XMLHttpRequestSynchronous);
         ThreadableLoader::loadResourceSynchronously(executionContext, request, *this, options, resourceLoaderOptions);
-    }
 
-    if (!m_exceptionCode && m_error)
-        m_exceptionCode = NetworkError;
-    if (m_exceptionCode)
-        exceptionState.throwDOMException(m_exceptionCode, "Failed to load '" + m_url.elidedString() + "'.");
+        if (!m_exceptionCode && m_error)
+            m_exceptionCode = NetworkError;
+        if (m_exceptionCode)
+            exceptionState.throwDOMException(m_exceptionCode, "Failed to load '" + m_url.elidedString() + "'.");
+    }
 }
 
 void XMLHttpRequest::abort()