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Before this implementation, specific status via former mergeOverlayIcon() was greyed out
with the visibility.
With this commit, the developer has two options:
a) override mergeGreyableOverlayIcons, in which case the overlay will
be greyed out when the item is greyed out as per former mergeOverlayIcon()
b) override mergeColorfulOverlayIcons, in which case the overlay will
be superimposed after the icon is greyed out as it is the case for stardard
error and recompute flags.
-Hide all visual properties of features when they are part of a body
-Propagate all body visual changes to features
-Separate display mode from body mode to enable setting display mode for both "tip" and "through" modes
-Use default visuals for body shape and only make "through" a new display mask mode for the children
- 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
