Picking near Earth sphere border returns pickIds equal to 255, 65535 which is being misinterpreted as object pick

Take a look at the following example:

Cesium.Camera.DEFAULT_VIEW_RECTANGLE = Cesium.Rectangle.fromDegrees(-40, -40, 40, 40);

var viewer = new Cesium.Viewer('cesiumContainer', {
    selectionIndicator : false,
    infoBox : false
});

var scene = viewer.scene;
var handler;

var i;
for (i = 0; i != 255; ++i) {
    viewer.entities.add({
        id: 'obj_' + i,
        /*
        polyline: {
            positions: Cesium.Cartesian3.fromDegreesArray(
                [Math.random() * 10, Math.random() * 10, Math.random() * 10, Math.random() * 10]),
            followSurface: false,
            material: Cesium.Color.RED,
          },
        */
        point: {
            color: Cesium.Color.RED
        },
        position: Cesium.Cartesian3.fromDegrees(Math.random() * 10, Math.random() * 10)
    });
}

handler = new Cesium.ScreenSpaceEventHandler(scene.canvas);
handler.setInputAction(function(movement) {
    var pickedObject = scene.pick(movement.endPosition);
    if (Cesium.defined(pickedObject)) {
        var cartesian = viewer.camera.pickEllipsoid(movement.endPosition, scene.globe.ellipsoid);
        if (cartesian) {
            var cartographic = Cesium.Cartographic.fromCartesian(cartesian);
            var longitudeString = Cesium.Math.toDegrees(cartographic.longitude).toFixed(2);
            var latitudeString = Cesium.Math.toDegrees(cartographic.latitude).toFixed(2);
            
            console.log(pickedObject.id._id + ' ' + movement.endPosition + ' (' + longitudeString + ', ' + latitudeString + ')');
        } else {
            console.log(pickedObject.id._id + ' ' + movement.endPosition);
        }
    }
}, Cesium.ScreenSpaceEventType.MOUSE_MOVE);

It displays points in [0, 10]x[0, 10] degrees square and on mouse move tries to pick entity under mouse cursor — if there is any, outputs mouse coordinates in the log.

Since all points in [0, 10]x[0, 10] degrees square it is expected that points will be picked only in it, which is not the case — if I move mouse near Earth sphere border I get some points selected:

(notice that last two columns in the log are selected point coordinates, and they are far outside [0, 10]x[0, 10] degrees square).

Same issue with polylines entities picking (and probably other entities types).

If I reduce number of entities to 253 or less I can’t reproduce this issue.

Tested in CesiumJS 1.28 in Firefox Developer Edition 52.0a2 and Chromium 55.0.2883.87 on Ubuntu 16.04 with NVidia GTX 980 with NVidia proprietary drivers 367.57.

[rutsky]

@pjcozzi done, please review: #4790

[pjcozzi]

Thanks again for the fix, @rutsky. I made a small tweak to also not render the sun, moon, and sky box and merged everything in #4806 since I could not commit to your branch (could have been an issue on my end).