'VIEW2D_OT' operators were not respected in WM_keymap_guess_opname().
This was seemingly done on purpose (see comment "Op types purposely
skipped for now"), but dont really see the reason for doing so.
Since the "View2D" keymap is not bound to a specific spacetype, we can
still find it using WM_keymap_find_all() [and passing 0 as spacetype] or
better use the dedicated WM_keymap_find_all_spaceid_or_empty().