- Moved all common code for part design features view providers to a base
class.
- Move shared code for Sketch based features to newly created
ViewProviderSketchBased class
- Add ViewProviderSketchBased to initialization
- Make Pad and Pocket ViewProviders to use the shared code
- Minor fixes to TaskFeatureParameters and some derived classes
Added a new class: TaskDlgFeatureBased which currently contains common
code for TaskDlgSketcherBasedParameters::reject() as well as the same
methode for TaskDlgDressUpParameters.
It's likely that other Feature task dialogs will inherit this class too.
