feat: make ipc-message and ipc-message-sync events public (#16468)

spec/api-web-contents-spec.js

@@ -995,6 +995,34 @@ describe('webContents module', () => {
     })
   })
 
+  describe('ipc-message event', () => {
+    it('emits when the renderer process sends an asynchronous message', async () => {
+      const webContents = remote.getCurrentWebContents()
+      const promise = emittedOnce(webContents, 'ipc-message')
+
+      ipcRenderer.send('message', 'Hello World!')
+
+      const [, channel, message] = await promise
+      expect(channel).to.equal('message')
+      expect(message).to.equal('Hello World!')
+    })
+  })
+
+  describe('ipc-message-sync event', () => {
+    it('emits when the renderer process sends a synchronous message', async () => {
+      const webContents = remote.getCurrentWebContents()
+      const promise = emittedOnce(webContents, 'ipc-message-sync')
+
+      ipcRenderer.send('handle-next-ipc-message-sync', 'foobar')
+      const result = ipcRenderer.sendSync('message', 'Hello World!')
+
+      const [, channel, message] = await promise
+      expect(channel).to.equal('message')
+      expect(message).to.equal('Hello World!')
+      expect(result).to.equal('foobar')
+    })
+  })
+
   describe('referrer', () => {
     it('propagates referrer information to new target=_blank windows', (done) => {
       const server = http.createServer((req, res) => {