bug#37944: 27.0.50; text-properties stop at newline rather than window

[Eli Zaretskii]

> From: Alex Branham <alex.branham@gmail.com>
> Date: Sun, 27 Oct 2019 08:50:12 -0400
> 
> For example, if you use ledger-mode the following transaction:
> 
> 2019-10-27 foo
>     Expenses:Rent                           $ 10.00
>     Assets:Checking
> 
> in Emacs 26.3 the face ledger-font-xact-highlight-face gets shown to the
> window's right edge but in Emacs built from git master it is only shown
> up through the newline character on each line. I've noticed this affects
> magit too and likely others. I skimmed through the NEWS file but didn't
> see anything about this; sorry if I've missed discussion elsewhere.

>From NEWS:

  ** New face attribute ':extend' to control face extension at EOL.
  The new face attribute ':extend' controls whether to use the face for
  displaying the empty space beyond end of line (EOL) till the edge of
  the window.  By default, this attribute is non-nil only for 'region',
  'secondary-selection', 'hl-line' and diff faces; any other face that
  crosses end of line will not affect the display of the empty space at EOL.