A better fix for extension of overlay string's faces

* src/xdisp.c (face_at_pos): Revert previous change that
rejected the underlying face if it failed the filtering
criteria.
* src/xfaces.c (face_at_string_position): Reset the base face's
attribute used for filtering faces if the attribute is t.
(Bug#38563)
1 job for master in 55 minutes and 26 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
failed #4497
test-all

00:55:26

 
Name Stage Failure
failed
test-all Test
make[2]: *** [check-doit] Error 1
Makefile:319: recipe for target 'check-doit' failed
make[2]: Leaving directory '/builds/emacs/emacs/test'
make[1]: *** [check-expensive] Error 2
Makefile:294: recipe for target 'check-expensive' failed
make[1]: Leaving directory '/builds/emacs/emacs/test'
make: *** [check-expensive] Error 2
Makefile:959: recipe for target 'check-expensive' failed
ERROR: Job failed: exit code 1