Tasker Scene WebView JavaScript Interaction

Question

Is it possible to call a Javascript function that exists within a WebView from Tasker? I tried calling a URL on the WebView of "javascript:FUNCTION_NAME()", but that did not seem to work.

This is a completely random example. Lets say, from Tasker, that I want to be able to change the background color of the body of the WebView.

In the webview, I have the code

<script>
function ChangeBGColor(NewColor)
{
document.body.style.backgroundColor=NewColor;
}
</script>

I want to be able to call ChangeBGColor() from Tasker with a color.