Set clip pointer to NULL when closing playlist

4 jobs from master in 2 minutes and 57 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #255037
amd64 debian
build-debian

00:00:49

passed #255038
macos
build-macos

00:01:12

passed #255040
win32 amd64 debian
build-win32

00:02:06

passed #255039
win64 amd64 debian
build-win64

00:02:12