Merge branch 'qt_list_ctrl_hit_test_offset' of https://github.com/GeoTeric/wxWidgets into qt-listctrl

Fix wxListCtrl::HitTest() which was off roughly by 1 due to not taking
into account the header height.

Closes https://github.com/wxWidgets/wxWidgets/pull/1350

samples/listctrl/listtest.h

@@ -78,7 +78,7 @@ public:
     virtual bool IsItemChecked(long item) const wxOVERRIDE;
 
 private:
-    void ShowContextMenu(const wxPoint& pos);
+    void ShowContextMenu(const wxPoint& pos, long item);
     wxLog *m_logOld;
     void SetColumnImage(int col, int image);