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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
web_contents()->FocusThroughTabTraversal(reverse);
}
bool WebContents::SendIPCMessage(bool all_frames,
                                 const base::string16& channel,
                                 const base::ListValue& args) {
  return Send(new AtomViewMsg_Message(routing_id(), all_frames, channel, args));
}
void WebContents::SendInputEvent(v8::Isolate* isolate,
                                 v8::Local<v8::Value> input_event) {
  const auto view = web_contents()->GetRenderWidgetHostView();
  if (!view)
    return;
  const auto host = view->GetRenderWidgetHost();
  if (!host)
    return;
  int type = mate::GetWebInputEventType(isolate, input_event);
  if (blink::WebInputEvent::isMouseEventType(type)) {
    blink::WebMouseEvent mouse_event;
    if (mate::ConvertFromV8(isolate, input_event, &mouse_event)) {
      host->ForwardMouseEvent(mouse_event);
      return;
    }
  } else if (blink::WebInputEvent::isKeyboardEventType(type)) {
    content::NativeWebKeyboardEvent keyboard_event;
    if (mate::ConvertFromV8(isolate, input_event, &keyboard_event)) {
      host->ForwardKeyboardEvent(keyboard_event);
      return;
    }
  } else if (type == blink::WebInputEvent::MouseWheel) {