Previous fix to resolve GPU hang which could occur in the
Metal backend caused additional flickering to occur as
as side effect, due to removal of required execution
dependencies in certain places.
This patch resolves both problems by only removing the
GPU hang dependency stall when additional synchronization
primitives are used along-side the global sync primitive.
Authored by Apple: Michael Parkin-White
Pull Request: https://projects.blender.org/blender/blender/pulls/106914
2745cacd95