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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
const content::NotificationSource& source,
                          const content::NotificationDetails& details) {
  switch (type) {
    case content::NOTIFICATION_NAV_ENTRY_PENDING: {
      content::NavigationEntry* entry =
          content::Details<content::NavigationEntry>(details).ptr();
      content::NavigationEntryImpl* entry_impl =
          static_cast<content::NavigationEntryImpl*>(entry);
      
      
      
      
      
      
      if (entry_impl->frame_tree_node_id() == -1) {
        deferred_load_url_.id = entry->GetUniqueID();
      }
      break;
    }
    default:
      NOTREACHED();
      break;
  }
}
void WebContents::DevToolsReloadPage() {