WallGeometry has incorrect texture coordinates

[hpinkos]

Reported on the forum: https://groups.google.com/forum/?hl=en#!topic/cesium-dev/lUUFr2-LvGc

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

var material = new Cesium.ImageMaterialProperty({
    image: '../images/Cesium_Logo_overlay.png',
    repeat: new Cesium.Cartesian2(1.0, 1.0)
});

var wall_1 = viewer.entities.add({
    id: 'wall_1',
    name: 'Two-position wall',
    wall: {
        positions: Cesium.Cartesian3.fromDegreesArray([
            -110.0, 38.0,
            -109.0, 38.0]),
        maximumHeights: [ 10000.0, 10000.0 ],
        minimumHeights: [     0.0,     0.0 ],
        material: material
    }
});

var wall_2 = viewer.entities.add({
    id: 'wall_2',
    name: 'Three-position wall',
    wall: {
        positions: Cesium.Cartesian3.fromDegreesArray([
            -110.0, 39.0,
            -109.5, 39.0,
            -109.0, 39.0]),
        maximumHeights: [ 10000.0, 10000.0, 10000.0 ],
        minimumHeights: [     0.0,     0.0,     0.0 ],
        material: material
    }
});

viewer.zoomTo(wall_2);