Todd Volkert dae720bef4
Remove remaining uses of childToSlot (#64273)
The remaining uses of this pattern were all due to wanting to have
the child's slot when `Element.forgetChild()` was called. However,
when that method is called, the child's `slot` value is still valid
in the context of the parent, so the uses can just use `child.slot`.

This is the final round of cleanup from the fallout of #63269
2020-08-21 10:41:05 -07:00
..