- Electron version: 1.1.0
- Operating system: Windows
- Use case: cleanup and reporting tasks executed on quit (headless), which may take time and should not prevent from opening a new instance.
- Proposed solutions:
  - new _app.releaseSingleInstance()_ API which free the singleInstance lock
  - replace _app.releaseSingleInstance()_ API by an event listener (which may be listened/unlistened)
  - [app.makeSingleInstance](https://github.com/electron/electron/blob/master/docs/api/app.md#appmakesingleinstancecallback) returns the result of the callback function. So we can choose to quit or not in a more accurate way.
  - Provide a communication channel between the new instance and the main one (in callback arguments)

atom/browser/api/atom_api_app.cc
auto command_line = base::CommandLine::ForCurrentProcess();
  if (base::EndsWith(switch_string, "-path",
                     base::CompareCase::INSENSITIVE_ASCII) ||
      switch_string == switches::kLogNetLog) {
    base::FilePath path;
    args->GetNext(&path);
    command_line->AppendSwitchPath(switch_string, path);
    return;
  }
  std::string value;
  if (args->GetNext(&value))
    command_line->AppendSwitchASCII(switch_string, value);
  else
    command_line->AppendSwitch(switch_string);
}
#if defined(OS_MACOSX)
int DockBounce(const std::string& type) {
  int request_id = -1;
  if (type == "critical")
    request_id = Browser::Get()->DockBounce(Browser::BOUNCE_CRITICAL);
  else if (type == "informational")
    request_id = Browser::Get()->DockBounce(Browser::BOUNCE_INFORMATIONAL);
  return request_id;
}
void DockSetMenu(atom::api::Menu* menu) {
  Browser::Get()->DockSetMenu(menu->model());
}
#endif
void Initialize(v8::Local<v8::Object> exports, v8::Local<v8::Value> unused,