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* Electron version: 1.6.1
* Operating system: macOS

### Expected behavior

navigator.geolocation.getCurrentPosition runs in background

### Actual behavior

the entire UI is frozen

### How to reproduce

```js
    navigator.geolocation.getCurrentPosition((pos) => {
      console.log('POS: ' + pos);
    }, (err) => {
      console.log('Geolocation error: ', err);
    }, {enableHighAccuracy: false});
```
atom/browser/api/atom_api_web_contents.cc
if (type_ == REMOTE)
    return;
  managed_web_contents()->CloseDevTools();
}
bool WebContents::IsDevToolsOpened() {
  if (type_ == REMOTE)
    return false;
  return managed_web_contents()->IsDevToolsViewShowing();
}
bool WebContents::IsDevToolsFocused() {
  if (type_ == REMOTE)
    return false;
  return managed_web_contents()->GetView()->IsDevToolsViewFocused();
}
void WebContents::EnableDeviceEmulation(
    const blink::WebDeviceEmulationParams& params) {
  if (type_ == REMOTE)
    return;
  Send(new ViewMsg_EnableDeviceEmulation(routing_id(), params));
}
void WebContents::DisableDeviceEmulation() {
  if (type_ == REMOTE)
    return;
  Send(new ViewMsg_DisableDeviceEmulation(routing_id()));
}
void WebContents::ToggleDevTools() {