Correctly reindent previous line in electric-indent-mode

Correctly reindent previous line in electric-indent-mode

Fixes: bug#35254
Do this even when electric-indent-inhibit is t, except when the
newline insertion is being performed by electric-layout-mode.

* lisp/electric.el (electric-indent-post-self-insert-function):
Reindent previous line unless operating under
electric-layout-mode.
(electric-layout-post-self-insert-function-1): Bind
electric-indent-inhibit to 'electric-layout-mode.

* test/lisp/electric-tests.el
(electric-layout-control-reindentation): New test.