Tasker Scene WebView JavaScript Interaction

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 function ChangeBGColor(NewColor) { document.body.style.backgroundColor=NewColor; } I want to be able to call ChangeBGColor() from Tasker with a color.