How to Android WebView video fullscreen lock orientation

Screen orientation lock (screen.orientation.lock()) is not working in android webview.

function lockLandScape() {
    console.log(JSON.stringify(screen.orientation.lock))
    if (screen.orientation && screen.orientation.lock) {
      screen.orientation.lock('landscape');
    }
}
function unlockLandScape() {
    if (screen.orientation && screen.orientation.unlock) {
        screen.orientation.unlock()
    }
}   
function videoFullScreen(elem){
    if (elem.requestFullscreen) {
      elem.requestFullscreen();
    } else if (elem.mozRequestFullScreen) {
      elem.mozRequestFullScreen();
    } else if (elem.webkitRequestFullscreen) {
      elem.webkitRequestFullscreen();
    } else if (elem.msRequestFullscreen) { 
      elem.msRequestFullscreen();
    }
    elem.classList.add("fullscreen");
    lockLandScape()
}

Where elem is video element in webview.