For our project, we want to open our electron app from tray with a keypress on "Scroll Lock" (js keycode 145) but this is no registered accelerator that we can use.
atom/common/keyboard_util.cc
bool* shifted) {
  std::string str = base::ToLowerASCII(s);
  if (str == "ctrl" || str == "control") {
    return ui::VKEY_CONTROL;
  } else if (str == "super" || str == "cmd" || str == "command" ||
             str == "meta") {
    return ui::VKEY_COMMAND;
  } else if (str == "commandorcontrol" || str == "cmdorctrl") {
#if defined(OS_MACOSX)
    return ui::VKEY_COMMAND;
#else
    return ui::VKEY_CONTROL;
#endif
  } else if (str == "alt" || str == "option") {
    return ui::VKEY_MENU;
  } else if (str == "shift") {
    return ui::VKEY_SHIFT;
  } else if (str == "altgr") {
    return ui::VKEY_ALTGR;
  } else if (str == "plus") {
    *shifted = true;
    return ui::VKEY_OEM_PLUS;
  } else if (str == "capslock") {
    return ui::VKEY_CAPITAL;
  } else if (str == "numlock") {
    return ui::VKEY_NUMLOCK;
  } else if (str == "tab") {
    return ui::VKEY_TAB;
  } else if (str == "num0") {