Implement incremental search in wxGenericListCtrl.

Mostly copy wxGenericTreeCtrl incremental search implementation to
wxGenericListCtrl (unfortunately there is no simple way to reuse this code
currently), including the recently added EnableBellOnNoMatch() method.

Update the sample to test it, the key event handling in it had to be modified
to allow it.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72639 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/listbase.h

@@ -454,6 +454,10 @@ public:
     bool InReportView() const { return HasFlag(wxLC_REPORT); }
     bool IsVirtual() const { return HasFlag(wxLC_VIRTUAL); }
 
+    // Enable or disable beep when incremental match doesn't find any item.
+    // Only implemented in the generic version currently.
+    virtual void EnableBellOnNoMatch(bool WXUNUSED(on) = true) { }
+
 protected:
     // Real implementations methods to which our public forwards.
     virtual long DoInsertColumn(long col, const wxListItem& info) = 0;