message: fix (again) frustum-box intersection
  We were early-exiting too aggressively in the some case.
diff: @@ -836,10 +836,23 @@ size_t ShadowMap::intersectFrustumWithBox(
  }
  }
  - // if we have no vertices at this point, we can't have an intersection because
  - // no vertices of the frustum is in the box and not vertices of the box is in the frustum.
  + /*
  + * At this point it's possible to have zero vertices (i.e.: no vertices of the box
  + * are in the frustum and no vertices of the frustum are in the box) but both objects
  + * have a non-null intersection, e.g.:
  + *
  + * +--------+
  + * | |
  + * +----|--------|---+
  + * | | | |
  + * | | | |
  + * | | | |
  + * +----|--------|---+
  + * | |
  + * +--------+
  + *
  + */
  - if (vertexCount) {
  /*
  * It's not enough here to have all 8 vertices, consider this:
  *
  @@ -876,7 +889,6 @@ size_t ShadowMap::intersectFrustumWithBox(
  wsFrustumCorners, wsSceneReceiversCorners.vertices);
  }
  }
  - }
  assert_invariant(vertexCount <= outVertices.size());
  