fix(types): add missing types for removing event listeners (#2307)

Author: JoelEinbinder

utils/generate_types/index.js

@@ -159,7 +159,7 @@ function createEventDescriptions(classDesc) {
 function classBody(classDesc) {
   const parts = [];
   const eventDescriptions = createEventDescriptions(classDesc);
-  for (const method of ['on', 'once', 'addListener']) {
+  for (const method of ['on', 'once', 'addListener', 'removeListener', 'off']) {
     for (const {eventName, params, comment} of eventDescriptions) {
         if (comment)
           parts.push(writeComment(comment, '  '));

utils/generate_types/test/test.ts

@@ -88,6 +88,7 @@ playwright.chromium.launch().then(async browser => {
 
 import * as crypto from 'crypto';
 import * as fs from 'fs';
+import { EventEmitter } from 'events';
 
 playwright.chromium.launch().then(async browser => {
   const page = await browser.newPage();
@@ -729,3 +730,14 @@ playwright.chromium.launch().then(async browser => {
   // Register the engine. Selectors will be prefixed with "tag=".
   await playwright.selectors.register('tag', createTagNameEngine);
 })();
+
+// Event listeners
+(async function() {
+  const eventEmitter = {} as (playwright.Page|playwright.BrowserContext|EventEmitter);
+  const listener = () => {};
+  eventEmitter.addListener('close', listener)
+              .on('close', listener)
+              .once('close', listener)
+              .removeListener('close', listener)
+              .off('close', listener);
+});