In `ui_popup_block_position` popup blocks are scaled with the owner
button region scale which wasn't being done for layout panel bounds.
This applies the scale applied to the popup block to layout panels
bodies and headers.
Also when calculating layout-panels headers and bodies the offset
`layout_panel_y_offset` is applied in place, this because this value
can also be affected by this scale.
This solves the original issue described in #122411 and reverts the
regression #123807.
Ref !123980
262c68512f