Added missing release.

git-svn-id: svn://10.0.0.236/trunk@35937 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/xpcom/threads/nsThread.cpp

@@ -547,6 +547,7 @@ nsThreadPoolRunnable::Run()
                ("nsIThreadPool thread %p running %p\n", th, this));
         rv = request->Run();
         NS_ASSERTION(NS_SUCCEEDED(rv), "runnable failed");
+        NS_RELEASE(request);
 
         // let the thread pool know we've finished a run
         PR_CEnterMonitor(mPool);