If editor contains nested editable components and the native selection enters (#692)
If editor contains nested editable components and the native selection enters (#692)

one of these, focus moves from the `Content` DOM element to the new active
element but editor doesn't really lose focus and selection must not be blurred.
ianstormtaylor/slate,isubastiCadmus/slate,ashutoshrishi/slate,6174/slate,ianstormtaylor/slate,AlbertHilb/slate