System Information
Operating system: Linux-4.4.0-148-generic-x86_64-with-debian-stretch-sid 64 Bits
Graphics card: GeForce GTX 1080/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 418.56

Blender Version
Broken: version: 2.80 (sub 74), branch: master, commit date: 2019-06-12 07:01, hash: rBfd2e143eaff8
Worked: 2.79

Short description of error
Parenting a mask to a tracker does not seem to work. Even though the Active Point panel lists the marker that the mask point was parented to, when playing back the clip the mask does not move with the Track.
However, once I save the file and reopen it, the mask is moving together with the Track it was parented to. Seems like some despgraph update is missing?
Exact steps for others to reproduce the error
Obviously I can't upload a file that shows the bug, because after saving it works correctly.
So, open Blender, load a clip, track a marker.
Then create a mask, select one or all points of the mask, hit Ctrl+P.
On playback the mask will not move with the Track.
Save the file and reopen and it should work.