Fix Detail Highlight when Detail has no Geometry

- Detail circles were no drawn if detail area did not
  produce any geometry (detail anchor point + radius not
  over original part.

src/Mod/TechDraw/Gui/QGIViewPart.cpp

@@ -331,6 +331,8 @@ void QGIViewPart::drawViewPart()
         return;
     }
     if (!viewPart->hasGeometry()) {
+        removePrimitives();                      //clean the slate
+        removeDecorations();
         return;
     }
 
@@ -754,10 +756,6 @@ void QGIViewPart::drawHighlight(TechDraw::DrawViewDetail* viewDetail, bool b)
         return;
     }
 
-    if (!viewDetail->hasGeometry()) {
-        return;
-    }
-
     auto vp = static_cast<ViewProviderViewPart*>(getViewProvider(getViewObject()));
     if ( vp == nullptr ) {
         return;