Billboard were cutted off at edge of earth in android brower

Forgive my poor english! When billboad at the edge of the map, it will be cutted off. Only in android webview.
Move the billboad to edge, now its fine

**then move top just a little, some billboard shoud be hide. But part of it were cutted off.**

**In IOS safari , no problem like above.**

Source code
```javascript
var viewer = new Cesium.Viewer('cesiumContainer', {
selectionIndicator : true,
infoBox : false,
animation: false,
scene3DOnly: true,
selectionIndicator: false,
baseLayerPicker: false,
timeline: false,
homeButton: false,
fullscreenButton: false,
navigationInstructionsInitiallyVisible: false,
navigationHelpButton: false,
geocoder: false
});
viewer.scene.globe.depthTestAgainstTerrain = false;
viewer.scene.fxaa = true;
viewer.scene.postProcessStages.fxaa.enabled = true;
$.getJSON ("./data/demo.json", function (result) {
result.data.forEach(function(value,index,array){
viewer.entities.add({
name : value.name,
position: Cesium.Cartesian3.fromDegrees(value.longitude, value.latitude), //
billboard: {
image: "./images/target.png",
color: getStatus(value.status),
verticalOrigin: Cesium.VerticalOrigin.BOTTOM,
sizeInMeters: false,
scale: 0.5,
scaleByDistance: new Cesium.NearFarScalar(1.5e2, 1.5, 1.0e6, 1.0),
heightReference: Cesium.HeightReference.CLAMP_TO_GROUND,
},
});
})
```
Thanks

Start by reproducing the issue with the provided Cesium.Viewer setup, billboard configuration, data/demo.json, and images/target.png in an Android WebView. Compare billboards positioned at the map edge with the same case in iOS Safari. Done means edge billboards are not incorrectly clipped in Android WebView.

Written by the indexing model from the issue text.