Blender Git Loki

Make dopesheet settings per-tracking data

It was a bit confusing to synchronize settings used in pre-calculated
dopesheet channels which was storing in tracking data with settings
used for display which is in space data.

This was initially done by converting one flags to other and checking
if space's settings matches pre-calculated one, but that had several
issues if two different dopesheet are using different settings:

- Channels would be re-calculated on every redraw for each of spaces
- Dopesheet operators could fail due to the could be using channels
calculated for other space.

That was also quite nasty code checking if requested settings matches
pre-calculated one.