Draft: add onChanged method in the derived annotation classes

The classes `ViewProviderDimensionBase`, `ViewProviderLinearDimension`,
`ViewProviderAngularDimension`, `ViewProviderText`, and
`ViewProviderLabel` use `super()` to call the `onChanged` method
of the parent class `ViewProviderDraftAnnotation`.

In this way the `AnnotationStyle` property correctly modifies
the properties of every annotation object.

src/Mod/Draft/draftviewproviders/view_dimension.py

@@ -265,8 +265,8 @@ class ViewProviderDimensionBase(ViewProviderDraftAnnotation):
         return
 
     def onChanged(self, vobj, prop):
-        """called when a view property has changed"""
-        return
+        """Execute when a view property is changed."""
+        super(ViewProviderDimensionBase, self).onChanged(vobj, prop)
 
     def doubleClicked(self,vobj):
         self.setEdit(vobj)
@@ -559,7 +559,9 @@ class ViewProviderLinearDimension(ViewProviderDimensionBase):
                 self.line.coordIndex.setValues(0,4,(0,1,2,3))
 
     def onChanged(self, vobj, prop):
-        """called when a view property has changed"""
+        """Execute when a view property is changed."""
+        super(ViewProviderLinearDimension, self).onChanged(vobj, prop)
+
         if prop == "ScaleMultiplier" and hasattr(vobj, "ScaleMultiplier"):
             # update all dimension values
             if hasattr(self,"font"):
@@ -936,6 +938,9 @@ class ViewProviderAngularDimension(ViewProviderDimensionBase):
                 obj.Angle = a
 
     def onChanged(self, vobj, prop):
+        """Execute when a view property is changed."""
+        super(ViewProviderAngularDimension, self).onChanged(vobj, prop)
+
         if hasattr(vobj, "ScaleMultiplier"):
             if vobj.ScaleMultiplier == 0:
                 return

src/Mod/Draft/draftviewproviders/view_label.py

@@ -276,7 +276,10 @@ class ViewProviderLabel(ViewProviderDraftAnnotation):
         text.getBoundingBox(b)
         return b.getBoundingBox().getSize().getValue()
 
-    def onChanged(self,vobj,prop):
+    def onChanged(self, vobj, prop):
+        """Execute when a view property is changed."""
+        super(ViewProviderLabel, self).onChanged(vobj, prop)
+
         if prop == "ScaleMultiplier":
             if not hasattr(vobj,"ScaleMultiplier"):
                 return

src/Mod/Draft/draftviewproviders/view_text.py

@@ -162,8 +162,10 @@ class ViewProviderText(ViewProviderDraftAnnotation):
             self.trans.translation.setValue(obj.Placement.Base)
             self.trans.rotation.setValue(obj.Placement.Rotation.Q)
 
+    def onChanged(self, vobj, prop):
+        """Execute when a view property is changed."""
+        super(ViewProviderText, self).onChanged(vobj, prop)
 
-    def onChanged(self,vobj,prop):
         if prop == "ScaleMultiplier":
             if "ScaleMultiplier" in vobj.PropertiesList:
                 if vobj.ScaleMultiplier: