Radix Dialog's RemoveScroll blocks wheel events on elements outside the
Dialog's DOM tree. The GIF picker Popover was portaling to document.body,
placing it outside the RemoveScroll boundary. Trackpad scrolling was
blocked while scrollbar dragging still worked.
Added PortalContainerContext so PopoverContent can portal into the modal
element instead of document.body when rendered inside a dialog/modal.
Lemon
54c4d7e47c