refactor: add emitCustomEvent() helper (#17960)

lib/browser/api/web-contents.js

@@ -350,22 +350,6 @@ WebContents.prototype._init = function () {
     })
   })
 
-  const forwardedEvents = [
-    'desktop-capturer-get-sources',
-    'remote-require',
-    'remote-get-global',
-    'remote-get-builtin',
-    'remote-get-current-window',
-    'remote-get-current-web-contents',
-    'remote-get-guest-web-contents'
-  ]
-
-  for (const eventName of forwardedEvents) {
-    this.on(eventName, (event, ...args) => {
-      app.emit(eventName, event, this, ...args)
-    })
-  }
-
   this.on('crashed', (event, ...args) => {
     app.emit('renderer-process-crashed', event, this, ...args)
   })