this._focusTimer = null;
          this.startOnFocusDelay();
          event.preventDefault();
        }
        break;

      case "blur":
        this.onBlur();
        break;

      case "focus":
        this.onFocus();
        break;

      case "unload":
        this.onUnload();
        break;
    }
  },

  onBlur() {
    this.disableDialog();
    // If we blur while waiting to enable the buttons, just cancel the
    // timer to ensure the delay doesn't fire while not focused.
    if (this._focusTimer) {
      this._focusTimer.cancel();
      this._focusTimer = null;
    }
  },

  onFocus() {
    this.startOnFocusDelay();
  },

  onUnload() {
    this.focusTarget.removeEventListener("blur", this);
    this.focusTarget.removeEventListener("focus", this);
    this.focusTarget.removeEventListener("keyup", this, true);
    this.focusTarget.removeEventListener("keydown", this, true);
    this.focusTarget.removeEventListener("unload", this);

    if (this._focusTimer) {
      this._focusTimer.cancel();
      this._focusTimer = null;
    }

    this.focusTarget = this.enableDialog = this.disableDialog = null;
  },

  startOnFocusDelay() {
    if (this._focusTimer) {
      return;
    }

    this._focusTimer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
    this._focusTimer.initWithCallback(
      () => {
        this.onFocusTimeout();
      },
      this.delayTime,
      Ci.nsITimer.TYPE_ONE_SHOT
    );
  },

  onFocusTimeout() {
    this._focusTimer = null;
    this.enableDialog();
  },
};

function makeSafe(fn) {
  return function () {
    // The dialog could be gone by now (if the user closed it),
    // which makes it likely that the given fn might throw.
    try {
      fn();
    } catch (e) {
      console.error(e);
    }
  };
}
PK