Make wxEventLoop::AddSourceForFD() static.

Any event sources should be registered with all the event loops, including the
ones that will be started in the future, and not only the current (and
potentially not even existing yet) one. So make AddSourceForFD() method static.

To still allow it to do different things in console and GUI applications, as
it must, virtualize it via the new wxEventLoopSourcesManager class which has
different implementations in the two cases, returned via wxAppTraits as usual.

Notice that this required moving the implementation of this method from
src/osx/core/evtloop_cf.cpp to src/osx/core/utilsexc_cf.cpp as the former file
is base-only and didn't have access to wxGUIAppTraits.

See #10258.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74341 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/evtloop.h

@@ -79,9 +79,9 @@ public:
 
 #if wxUSE_EVENTLOOP_SOURCE
     // create a new event loop source wrapping the given file descriptor and
-    // start monitoring it
-    virtual wxEventLoopSource *
-      AddSourceForFD(int fd, wxEventLoopSourceHandler *handler, int flags) = 0;
+    // monitor it for events occurring on this descriptor in all event loops
+    static wxEventLoopSource *
+      AddSourceForFD(int fd, wxEventLoopSourceHandler *handler, int flags);
 #endif // wxUSE_EVENTLOOP_SOURCE
 
     // dispatch&processing
@@ -296,19 +296,6 @@ public:
     wxGUIEventLoop() { m_impl = NULL; }
     virtual ~wxGUIEventLoop();
 
-#if wxUSE_EVENTLOOP_SOURCE
-    // We need to define a base class pure virtual method but we can't provide
-    // a generic implementation for it so simply fail.
-    virtual wxEventLoopSource *
-    AddSourceForFD(int WXUNUSED(fd),
-                   wxEventLoopSourceHandler * WXUNUSED(handler),
-                   int WXUNUSED(flags))
-    {
-        wxFAIL_MSG( "support for event loop sources not implemented" );
-        return NULL;
-    }
-#endif // wxUSE_EVENTLOOP_SOURCE
-
     virtual void ScheduleExit(int rc = 0);
     virtual bool Pending() const;
     virtual bool Dispatch();