corrected warnings when compiling with -Wall -W

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@15412 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/accel.cpp

@@ -59,6 +59,7 @@ public:
     }
 
     wxAccelRefData(const wxAccelRefData& data)
+        : wxObjectRefData()
     {
         m_accels.DeleteContents(TRUE);
         m_accels = data.m_accels;