[patch] fix for checking the command ambiguousness.

[Tom Tromey]

>>>>> "Pedro" == Pedro Alves <palves@redhat.com> writes:

Pedro> As the test uses Python stuff to expose the bug, I'd appreciate
Pedro> it if a Python person took a look.

Pedro> Is this only triggerable with Python?  If so, why?

I looked, and there aren't many callers of lookup_cmd_composition:
maintenance_do_deprecate, deprecated_cmd_warning, and gdbpy_parameter.
The last one is the path the test case takes.

Tom