Why not webview?

[HughIsaacs2]

I saw in the document that this is based on the Chrome Apps WebView API, why not just stick with <webview> why change it to <controlledframe>?

I get why this isn't an <iframe> attribute, but I don't get why <webview> doesn't suffice here.

I'm sorry if this is covered anywhere, I couldn't find anything that explained why the name choice.