3D Tiles refinement broken when skip LODs is disabled

[bagnell]

var viewer = new Cesium.Viewer('cesiumContainer');

var tileset = viewer.scene.primitives.add(new Cesium.Cesium3DTileset({
    url : 'https://beta.cesium.com/api/assets/1458?access_token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJqdGkiOiIxYmJiNTAxOC1lOTg5LTQzN2EtODg1OC0zMWJjM2IxNGNlYmMiLCJpZCI6NDQsImFzc2V0cyI6WzE0NThdLCJpYXQiOjE0OTkyNjM4MjB9.1WKijRa-ILkmG6utrhDWX6rDgasjD7dZv-G5ZyCmkKg',
    skipLevelOfDetail : false
}));

tileset.readyPromise.then(function() {
    var boundingSphere = tileset.boundingSphere;
    viewer.camera.viewBoundingSphere(boundingSphere, new Cesium.HeadingPitchRange(Cesium.Math.PI_OVER_TWO, -0.5, boundingSphere.radius * 0.1));
    viewer.camera.lookAtTransform(Cesium.Matrix4.IDENTITY);
}).otherwise(function(error) {
    throw(error);
});

[bagnell]

If you try the example, the tileset won't refine until the camera is moved.

[pjcozzi]

@lilleyse can you please look at this? Perhaps this was broken with the recent fix in 1.37?

Please make sure there are enough unit tests and hooks into tile traversal to reasonably test.