== WebCore class renames == * Frame → BrowsingContext * FrameView → BrowsingContextView * Page → View | Tab | MainBrowsingContextHolder * RenderView → RenderRoot (also needs some functionality split out for SVG foreign object support) * ScriptController→ DOMWindowProxy * JSDOMWindowShell → JSDOMWindowProxy * DatasetDOMStringMap → DOMStringMap * FrameLoader → ? * SubframeLoader → ? * DocumentLoader → ? * ThreadableLoader → ? * DocumentThreadableLoader → ? * WorkerThreadableLoader → ? * RuntimeEnabledFeatures → DeprecatedRuntimeEnabledFeatures