I do a lot of HTML generation just with JavaScript and am finding myself creating `index.html` files that have code that looks like this:

     <!DOCTYPE html><html><head><script src="index.js"></script></head><body></body></html>

It would be nice to be able to do:

     browserWindow.loadHTML('<!DOCTYPE html><html><head><script src="index.js"></script></head><body></body></html>');

It would be even more awesome to do:

     browserWindow.loadScript(pathToScript);

I tried to use the `preload` option for `BrowserWindow` and using `loadURL('about:blank')`, but this has an unintended side effect of not allowing you to reference other script or CSS files using relative paths.

What do you think about proposed feature?
atom/browser/api/atom_api_web_contents.cc
session = Session::FromPartition(isolate, "");
  }
  session_.Reset(isolate, session.ToV8());
  content::WebContents* web_contents;
  if (IsGuest()) {
    scoped_refptr<content::SiteInstance> site_instance =
        content::SiteInstance::CreateForURL(
            session->browser_context(), GURL("chrome-guest://fake-host"));
    content::WebContents::CreateParams params(
        session->browser_context(), site_instance);
    guest_delegate_.reset(new WebViewGuestDelegate);
    params.guest_delegate = guest_delegate_.get();
    web_contents = content::WebContents::Create(params);
  } else if (IsOffScreen()) {
    bool transparent = false;
    options.Get("transparent", &transparent);
    content::WebContents::CreateParams params(session->browser_context());
    auto* view = new OffScreenWebContentsView(
        transparent, base::Bind(&WebContents::OnPaint, base::Unretained(this)));
    params.view = view;
    params.delegate_view = view;
    web_contents = content::WebContents::Create(params);
    view->SetWebContents(web_contents);
  } else {
    content::WebContents::CreateParams params(session->browser_context());
    web_contents = content::WebContents::Create(params);
  }
  InitWithSessionAndOptions(isolate, web_contents, session, options);
}
void WebContents::InitWithSessionAndOptions(v8::Isolate* isolate,