Repair test failures stemming from Android merge

Repair test failures stemming from Android merge

* lisp/kmacro.el (kmacro-step-edit-query)
(kmacro-step-edit-pre-command): Use `dummy-event' instead of
[nil] to continue a kbd macro; this is because nil now has a
function key map.
* src/androidfns.c (Fx_hide_tip): Allow calling this as a stub.
* src/fileio.c (Finsert_file_contents): In adherence to the
documentation, forbid supplying a BEG offset even for seekable
files, i.e. /dev/urandom on Linux kernel based systems.