Don't generate wxEVT_LIST_ITEM_RIGHT_CLICK outside of item area

Make wxGenericListCtrl used under wxGTK and wxOSX behave the same as the
native wxMSW wxListCtrl and wxTreeCtrl under all platforms and only generate
ITEM_RIGHT_CLICK events when an item was actually clicked, i.e. don't generate
them for the clicks completely outside of the client area.

Closes #4711.

docs/changes.txt

@@ -150,6 +150,7 @@ wxGTK:
 - Fix clearing of wxComboBox with wxCB_READONLY (Chuddah).
 - Fix setting "pressed" bitmap for wxToggleButton (Kevin B. McCarty).
 - Fix GTK+ warnings for wxFileDialog with wxFD_MULTIPLE style.
+- Don't generate wxEVT_LIST_ITEM_RIGHT_CLICK outside of item area (Igor Korot).
 
 wxMSW:
 

samples/listctrl/listtest.cpp

@@ -936,6 +936,8 @@ wxBEGIN_EVENT_TABLE(MyListCtrl, wxListCtrl)
     EVT_LIST_ITEM_ACTIVATED(LIST_CTRL, MyListCtrl::OnActivated)
     EVT_LIST_ITEM_FOCUSED(LIST_CTRL, MyListCtrl::OnFocused)
 
+    EVT_LIST_ITEM_RIGHT_CLICK(LIST_CTRL, MyListCtrl::OnItemRightClick)
+
     EVT_LIST_COL_CLICK(LIST_CTRL, MyListCtrl::OnColClick)
     EVT_LIST_COL_RIGHT_CLICK(LIST_CTRL, MyListCtrl::OnColRightClick)
     EVT_LIST_COL_BEGIN_DRAG(LIST_CTRL, MyListCtrl::OnColBeginDrag)
@@ -1118,6 +1120,13 @@ void MyListCtrl::OnFocused(wxListEvent& event)
     event.Skip();
 }
 
+void MyListCtrl::OnItemRightClick(wxListEvent& event)
+{
+    LogEvent(event, wxT("OnItemRightClick"));
+
+    event.Skip();
+}
+
 void MyListCtrl::OnListKeyDown(wxListEvent& event)
 {
     long item;

samples/listctrl/listtest.h

@@ -61,6 +61,7 @@ public:
     void OnListKeyDown(wxListEvent& event);
     void OnActivated(wxListEvent& event);
     void OnFocused(wxListEvent& event);
+    void OnItemRightClick(wxListEvent& event);
     void OnCacheHint(wxListEvent& event);
 
     void OnChar(wxKeyEvent& event);

src/generic/listctrl.cpp

@@ -2432,8 +2432,6 @@ void wxListMainWindow::OnMouse( wxMouseEvent &event )
         // outside of any item
         if (event.RightDown())
         {
-            SendNotify( (size_t) -1, wxEVT_LIST_ITEM_RIGHT_CLICK, event.GetPosition() );
-
             wxContextMenuEvent evtCtx(
                 wxEVT_CONTEXT_MENU,
                 GetParent()->GetId(),