- Electron version: v0.36.9
- Operating system: Windows 10/OS X

In #779 a `disposition` was added to the `new-window` event in [webContents](https://github.com/atom/electron/blob/master/docs/api/web-contents.md#event-new-window) but it always seems to be set to `new-window` when clicking on target="_blank" links in our web app wrapper: https://github.com/irccloud/irccloud-desktop/blob/v0.1.3/app/main.js#L109

If I Ctrl (Win) or Cmd (OS X) or middle click on links, I would expect to see a `background-tab` disposition, as in Chrome that will open links in a background tab, while keeping focus on the current tab. I'd like to catch this behaviour to set `activate` to false in `shell.openExternal`.

Is this possible?

atom/browser/atom_browser_client.h
content::ResourceType resource_type,
      bool overridable,
      bool strict_enforcement,
      bool expired_previous_decision,
      const base::Callback<void(bool)>& callback,
      content::CertificateRequestResultType* request) override;
  void SelectClientCertificate(
      content::WebContents* web_contents,
      net::SSLCertRequestInfo* cert_request_info,
      scoped_ptr<content::ClientCertificateDelegate> delegate) override;
  void ResourceDispatcherHostCreated() override;
  
  brightray::BrowserMainParts* OverrideCreateBrowserMainParts(
      const content::MainFunctionParams&) override;
  void WebNotificationAllowed(
      int render_process_id,
      const base::Callback<void(bool)>& callback) override;
  
  void RenderProcessHostDestroyed(content::RenderProcessHost* host) override;
 private:
  
  std::map<int, int> pending_processes_;
  scoped_ptr<AtomResourceDispatcherHostDelegate>
      resource_dispatcher_host_delegate_;
  Delegate* delegate_;
  DISALLOW_COPY_AND_ASSIGN(AtomBrowserClient);
};
}  
#endif