* src/xdisp.c (syms_of_xdisp): New var `redisplay_skip_initial_frame`.

* src/xdisp.c (syms_of_xdisp): New var `redisplay_skip_initial_frame`.

This makes it possible to run most of the redisplay code (tho not the
actual drawing since there's nowhere to draw) even when there's no
real frame at hand, as is the case in batch mode.
This makes `xdisp-tests--minibuffer-resizing` work even in batch.

(redisplay_internal): Obey it.
(init_xdisp): Set `echo_area_window` even in noninteractive mode.
* src/dispnew.c (update_frame): Skip the initial frame.
* src/frame.c (make_frame): Use 80x25 as the default initial size.

* test/src/xdisp-tests.el (xdisp-tests--minibuffer-resizing):
Use the new var and fix use of `executing-kbd-macro`.