Fixes #3344. OnResizeNeeded using Top's Bounds for Top.

[tig]

Fixes

• Fixes A full-screen Modal view should not be movable/sizable #3344

Proposed Changes/Todos

• Only border drags now, not margin.
• Found, fixed, updated unit tests.

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[BDisp]

That the right way to manage the moveable of the view by handle it only on the Border. If has a Margin then the new position must take it at account. Good work.