multiple issues with managed insertBefore and replaceChild for cells

[thedavidmeister]

I'm really struggling to get insertBefore to work properly with cells (cells are the only reason to introduce the prototype overrides AFAICS).

Here's a few confusing examples:

Two cells provided for x and y.

 (let [parent (h/div)
       x (j/cell "foo")
       y (j/cell "bar")]
  (is (= y (.appendChild parent y)))
  (is (= x (.insertBefore parent x y))) ; <-- seems to do nothing

  (is (= "foobar" (.-textContent parent))))) ; <-- actually "bar"

Mixing cells with divs.

 (let [parent (h/div)
       x (j/cell "foo")
       y (h/div "bar")]
  (is (= y (.appendChild parent y)))
  (is (= x (.insertBefore parent x y))) ; <-- throws #object[Object Error: NotFoundError: DOM Exception 8]

  (is (= "foobar" (.-textContent parent))))) ; <-- actually "bar"

 (let [parent (h/div)
       x (h/div "foo")
       y (j/cell "bar")]
  (is (= y (.appendChild parent y)))
  (is (= x (.insertBefore parent x y))) ; <-- no error this time, fails silently

  (is (= "foobar" (.-textContent parent))))) ; <-- actually "bar"

i also couldn't see anywhere in hoplon that the managed insert logic is actually used.

are we overriding the prototype for no reason here?
how is this supposed to work?

first noticed as part of testing at #205

[thedavidmeister]

finding identical looking issues for replaceChild called for child cells

 (let [parent (h/div)
       x (j/cell "foo")
       y (j/cell "bar")]
  (is (= y (.appendChild parent y)))
  (is (= y (.replaceChild parent x y)))

  (is (= "foo" (.-textContent parent)))) ; <-- "bar" => failing silently

 (let [parent (h/div)
       x (j/cell "foo")
       y (h/div "bar")]
  (is (= y (.appendChild parent y)))
  (is (= y (.replaceChild parent x y))) ; <-- throws #object[Object Error: NotFoundError: DOM Exception 8]

  (is (= "foo" (.-textContent parent)))) ; <-- "bar"

 (let [parent (h/div)
       x (h/div "foo")
       y (j/cell "bar")]
  (is (= y (.appendChild parent y)))
  (is (= y (.replaceChild parent x y)))

  (is (= "foo" (.-textContent parent))))) ; <-- "bar" => failing silently