* src/data.c (Fmake_variable_frame_local): Remove

* src/data.c (Fmake_variable_frame_local): Remove

* src/lisp.h (struct Lisp_Buffer_Local_Value): Remove `frame_local'.

* src/data.c (swap_in_symval_forwarding, set_internal)
(set_symbol_trapped_write, make_blv, Fmake_variable_buffer_local)
(Fmake_local_variable, Fkill_local_variable, Flocal_variable_p):
Don't pay attention to ->frame_local any more.
(syms_of_data): Remove Qtrapping_frame_local and don't defsubr
Smake_variable_frame_local.

* etc/NEWS (Incompatible Lisp Changes in Emacs 26.1): Announce removal
of make-variable-frame-local.

* lisp/help-fns.el (describe-variable): Don't handle the now impossible
frame-local case.

* lisp/subr.el (make-variable-frame-local): Remove obsolescence data.

* src/frame.c (store_frame_param):
* src/eval.c (specbind): Don't pay attention to ->frame_local any more.

* src/widget.c (first_frame_p): Remove, unused.