Fix for bug # 58077 r=ducarroz sr=waterson

xpfe/components/urlbarhistory/src/nsUrlbarHistory.cpp

@@ -116,6 +116,11 @@ nsUrlbarHistory::~nsUrlbarHistory()
     {
         nsServiceManager::ReleaseService(kRDFServiceCID, gRDFService);
         gRDFService = nsnull;
+    }
+    if (gRDFCUtils)
+    {
+        nsServiceManager::ReleaseService(kRDFCUtilsCID, gRDFCUtils);
+        gRDFCUtils = nsnull;
     }
 	mDataSource = nsnull;
 	NS_IF_RELEASE(kNC_URLBARHISTORY);