A symbolic key event is generated, without specifying a hardware key.
Note: if the keysym is not present in the current keyboard map, the AtspiDeviceEventController instance has a limited
ability to generate such keysyms on-the-fly. Reliability of GenerateKeyboardEvent calls using out-of-keymap keysyms will vary from system
to system, and on the number of different out-of-keymap keysyms being generated in quick succession. In practice this is rarely
significant, since the keysyms of interest to AT clients and keyboard emulators are usually part of the current keymap, i.e., present on
the system keyboard for the current locale (even if a physical hardware keyboard is not connected).