FeatureRequest : Generalize goneMargin

[EaseTheWorld]

When views orders are like these and all are optional.

View1
(10dp margin between 1-2)
View2
(20dp margin between 2-3)
View3

If I set view3's layout_marginTop=20dp and layout_goneMarginTop=10dp(if view2 is gone)
but then it can't handle the case that both view1 and view2 are gone.

To satisfy the design specification, I wish I can specify each margin and anchor combination.
for View3
layout_constraintTop_toBottomWithMargin="@id/view2 20dp" // if view2 is visible
layout_constraintGoneMarginTop1="@id/view1 10dp" // if view2 is gone
layout_constraintGoneMarginTop2="parent 0dp" // if view1&2 is gone

Specifying margin and anchor(=constraint) together makes sense because
in ConstraintLayout, marginTop is no use without constraintTop.

I added number suffix Top1, Top2, ... because xml doesn't allow dupicate attribute.
and I know specifying reference and dimension together is against the rule and require 'string' type.
I think there would be better format than this.