Implement sending wxIconizeEvent in wxOSX.

Translate windowDid{Miniaturize,Deminiaturize} callbacks to calls to
SendIconizeEvent().

See #16718.

src/osx/toplevel_osx.cpp

@@ -229,3 +229,12 @@ void wxTopLevelWindowMac::SetRepresentedFilename(const wxString& filename)
 {
     m_nowpeer->SetRepresentedFilename(filename);
 }
+
+void wxTopLevelWindowMac::OSXSetIconizeState(bool iconize)
+{
+    if ( iconize != m_iconized )
+    {
+        m_iconized = iconize;
+        (void)SendIconizeEvent(iconize);
+    }
+}