Allow opening of webview in chrome extension

Question

I'm trying to create a responsive testing browser using chrome extension. Currently I'm using Iframes to render the web-contents. However iframes have a lot of issues opening third party websites in cross-domain origin sites. I found that webviews can quickly render the websites without any CORS or cookies issues. Is there any way in which I can use webviews in the chrome extension? Webviews are used by chrome apps which runs on chromium. So there might be some ways in which we can modify the chromium source code to allow webviews to open in extension.