[array] Remove invalid assertion in Array.p.reverse

Obvious in hindsight. The problem wasn't that a signaling nan snuck
into the array, but that equality comparisons always return false if
either operand is a nan.

Bug: chromium:900133
Change-Id: I9cf82afd1ad1fcc3bf7138b612f615b1bd51b98a
Reviewed-on: https://chromium-review.googlesource.com/c/1309634Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57159}

src/builtins/array-reverse.tq

@@ -49,8 +49,6 @@ module array {
   StoreElement<FastPackedDoubleElements, float64>(
       elements: FixedArrayBase, index: Smi, value: float64) {
     const elems: FixedDoubleArray = UnsafeCast<FixedDoubleArray>(elements);
-
-    assert(value == Float64SilenceNaN(value));
     StoreFixedDoubleArrayElementWithSmiIndex(elems, index, value);
   }