H/VBox layout h/vGrab doesn't work with resizeContainer=false

[CamilleLetavernier]

When using HBoxLayout + hGrab=true on the children, we expect child nodes to share the available space in the parent Hbox. However, if the parent HBox also specifies resizeContainer=false, it seems that all children get a size of 0 instead of being increased.

The same issue likely occurs for VBoxLayout + vGrab=true + resizeContainer=false, as both layouts are implemented in a similar way.