Backport of "player/play: Fix object construction and various leaks" into 1.20 (!2881) · Merge requests · GStreamer / gstreamer

Backport of !2880 (merged) "player/play: Fix object construction and various leaks".

Commits:

15ee056f player: Release signal adapter on finalize
abfbcc0b player: Fix object construction
f060b8b6 play: Fix object construction
aff79db6 play: Make ownership of video-sink clearer in combination with floating references
723bdd25 player: Don't leak wrapped video info

Backport of "player/play: Fix object construction and various leaks" into 1.20