Fix event object in wxSysColourChangedEvent.

The handler for this event in the base class incorrectly changed the event
object of the original event instead of setting it for the event being sent to
the window children as it was supposed to.

Closes #11458.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62818 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/wincmn.cpp

@@ -2479,7 +2479,7 @@ void wxWindowBase::OnSysColourChanged(wxSysColourChangedEvent& event)
         if ( !win->IsTopLevel() )
         {
             wxSysColourChangedEvent event2;
-            event.SetEventObject(win);
+            event2.SetEventObject(win);
             win->GetEventHandler()->ProcessEvent(event2);
         }