This allows to have annotation panels and grease pencil object panel at the same time.
The patch fix main issues:
- The get pointer functions were shared between GPencil object and Annotations. Now, these functions are different and the grease pencil version has been simplified.
- Some operators were shared and it was impossible detect what mode was running. Now the operators are different, and this allows to use different poll functions, but the exec code is shared using an internal parameter.
- The Annotation Tool was not available in GPencil Paint, Sculpt and Weignt Paint modes.
As result of this split, now both panels are visible and the tooltips are different.