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
zoom_controller_->SetZoomLevel(level);
}
double WebContents::GetZoomLevel() {
  return zoom_controller_->GetZoomLevel();
}
void WebContents::SetZoomFactor(double factor) {
  auto level = content::ZoomFactorToZoomLevel(factor);
  SetZoomLevel(level);
}
double WebContents::GetZoomFactor() {
  auto level = GetZoomLevel();
  return content::ZoomLevelToZoomFactor(level);
}
void WebContents::OnSetTemporaryZoomLevel(double level,
                                          IPC::Message* reply_msg) {
  zoom_controller_->SetTemporaryZoomLevel(level);
  double new_level = zoom_controller_->GetZoomLevel();
  AtomViewHostMsg_SetTemporaryZoomLevel::WriteReplyParams(reply_msg, new_level);
  Send(reply_msg);
}
void WebContents::OnGetZoomLevel(IPC::Message* reply_msg) {