Sets the scroll child for the scroll frame. The scroll child frame represents the (generally larger) area into which the scroll frame provides a (generally smaller) movable "window". The child must have an absolute size, set either by
<AbsDimension> in XML or using both
SetHeight() in Lua.
Setting a frame's scroll child involves changing the child frame's parent -- thus, if the frame's scroll child is protected, this operation cannot be performed while in combat.
frame- Reference to another frame to be the ScrollFrame's child. (