electron flow type definitions

Summary: Adding a flowtype library definition for electron 3 and fixing related type errors

Reviewed By: passy

Differential Revision: D9124758

fbshipit-source-id: e09cb5b05ba952e7f95f68f9043edc586f81ae83

src/ui/components/searchable/FilterToken.js

@@ -161,7 +161,8 @@ export default class FilterToken extends PureComponent<Props> {
     }
     const menu = electron.remote.Menu.buildFromTemplate(menuTemplate);
     const {bottom, left} = this._ref ? this._ref.getBoundingClientRect() : {};
-    menu.popup(electron.remote.getCurrentWindow(), {
+    menu.popup({
+      window: electron.remote.getCurrentWindow(),
       async: true,
       x: parseInt(left, 10),
       y: parseInt(bottom, 10) + 8,