vcl: make IconTestApp build with gcc 4.6

Change-Id: I5897a774b8949f336a40096a0727a347bae012ac

vcl/workben/icontest.cxx

@@ -115,6 +115,8 @@ public:
     virtual void Init() SAL_OVERRIDE;
     virtual int Main() SAL_OVERRIDE;
 
+    IconTestApp() : nRet(EXIT_SUCCESS) {};
+
 private:
     int nRet;